Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Tatsumi Ishihara Last modified date:2021.06.09

Professor / Functional Material Chemistry / Department of Applied Chemistry / Faculty of Engineering


Papers
1. Ran Gao, Abel Fernandez, Tanmoy Chakraborty, Aileen Luo, David Pesquera, Sujit Das, Gabriel Velarde, Vincent Thoréton, John Kilner, Tatsumi Ishihara, Slavomír Nemšák, Ethan J. Crumlin, Elif Ertekin, Lane W. Martin, Correlating Surface Crystal Orientation and Gas Kinetics in Perovskite Oxide Electrodes, Advanced Materials, 10.1002/adma.202100977, 2100977-2100977, 2021.04.
2. Huan Li, Takuya Kurihara, Dengyao Yang, Motonori Watanabe, Tatsumi Ishihara, A novel aqueous dual-ion battery using concentrated bisalt electrolyte, Energy Storage Materials, 10.1016/j.ensm.2021.03.029, 38, 454-461, 2021.06.
3. Junji Hyodo, Shogo Kato, Shintaro Ida, Tatsumi Ishihara, Yuji Okuyama, Takaaki Sakai, Determination of Oxide Ion Conductivity in Ba-Doped LaYbO3 Proton-Conducting Perovskites via an Oxygen Isotope Exchange Method, The Journal of Physical Chemistry C, 10.1021/acs.jpcc.0c09591, 125, 3, 1703-1713, 2021.01.
4. Masatoshi Ishida, Yogesh Kumar Maurya, Pingchun Wei, Takahide Shimada, Kazuhisa Yamasumi, Shigeki Mori, Ko Furukawa, Hajime Kusaba, Tatsumi Ishihara, Yongshu Xie, Hiroyuki Furuta, Chiral Interlocked Corrole Dimers Directly Linked at Inner Carbon Atoms of Confused Pyrrole Rings, Chemistry – An Asian Journal, 10.1002/asia.202100083, 2021.02.
5. Takaaki Sakai, Masako Ogushi, Kohei Hosoi, Atsushi Inoishi, Hidehisa Hagiwara, Shintaro Ida, Masatsugu Oishi, Tatsumi Ishihara, Characteristics of YCoO3-type perovskite oxide and application as an SOFC cathode, Journal of Materials Chemistry A, 10.1039/d0ta09487k, 9, 6, 3584-3588, 2021.02,

YCoO3 is discussed as a novel cathode material for solid oxide fuel cells (SOFCs).

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6. Atsushi Takagaki, Shohei Nakamura, Motonori Watanabe, Yoonyoung Kim, Jun Tae Song, Keiko Jimura, Kanta Yamada, Masaaki Yoshida, Shigenobu Hayashi, Tatsumi Ishihara, Enhancement of solid base activity for porous boron nitride catalysts by controlling active structure using post treatment, Applied Catalysis A: General, 10.1016/j.apcata.2020.117843, 608, 117843-117843, 2020.11.
7. Zhe Tan, Jun Tae Song, Atsushi Takagaki, Tatsumi Ishihara, Infiltration of cerium into a NiO–YSZ tubular substrate for solid oxide reversible cells using a LSGM electrolyte film, Journal of Materials Chemistry A, 10.1039/d0ta08564b, 9, 3, 1530-1540, 2021.01, NiO-Y2O3 stabilized ZrO2 (NiO-YSZ) supported tubular solid oxide cell, which consist of La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) dip-coated electrolyte film and Sm0.5Sr0.5CoO3-δ (SSC) air electrode, was prepared and power generation and electrolysis performance at intermediate temperature range were investigated. Among the rare earth oxides studied, infiltration of Ce nitrate into the substrate was the most effective for increasing cell performance in the case of 2 M infiltration. Moreover, it was found that the infiltration of higher concentration of Ce solution increased the maximum power density, because both IR loss and overpotential were significantly decreased. The maximum power density of the cell was 0.95 and 0.42 W cm-2 at 873 and 773 K, respectively at 3 M Ce nitrate infiltrated. The long-term stability of the cell was also measured by using the cell infiltrated with 1.5 M Ce, the stable power generation performance was demonstrated up to 100 h. The steam electrolysis performance of the cell using Ce infiltration was further studied and it was found that Ce also contributes to higher current density in SOEC operation and 1.07 A cm-2 at 1.6 V was achieved at 873 K using 2 M Ce infiltration..
8. Yu Wang, Ji Wu, Gang Wang, Dengyao Yang, Tatsumi Ishihara, Limin Guo, Oxygen Vacancy Engineering in Fe Doped Akhtenskite-Type MnO2 for Low-Temperature Toluene Oxidation, Applied Catalysis B: Environmental, 10.1016/j.apcatb.2020.119873, 285, 119873-119873, 2020.12.
9. Kwati Leonard, Wendelin Deibert, Mariya E. Ivanova, Wilhelm A. Meulenberg, Tatsumi Ishihara, Hiroshige Matsumoto, Processing Ceramic Proton Conductor Membranes for Use in Steam Electrolysis, Membranes, 10.3390/membranes10110339, 10, 11, 339-339, 2020.11, Steam electrolysis constitutes a prospective technology for industrial-scale hydrogen production. The use of ceramic proton-conducting electrolytes is a beneficial option for lowering the operating temperature. However, a significant challenge with this type of electrolyte has been upscaling robust planar type devices. The fabrication of such multi-layered devices, usually via a tape casting process, requires careful control of individual layers’ shrinkages to prevent warping and cracks during sintering. The present work highlights the successful processing of 50 × 50 mm2 planar electrode-supported barium cerium yttrium zirconate BaZr0.44Ce0.36Y0.2O2.9 (BZCY(54)8/92) half cells via a sequential tape casting approach. The sintering parameters of the half-cells were analyzed and adjusted to obtain defect-free half-cells with diminished warping. Suitably dense and gas-tight electrolyte layers are obtained after co-sintering at 1350 °C for 5 h. We then assembled an electrolysis cell using Ba0.5La0.5CoO3−δ as the steam electrode, screen printed on the electrolyte layer, and fired at 800 °C. A typical Ba0.5La0.5CoO3−δ|BaZr0.44Ce0.36Y0.2O3−δ(15 μm)|NiO-SrZr0.5Ce0.4Y0.1O3−δ cell at 600 °C with 80% steam in the anode compartment reached reproducible terminal voltages of 1.4 V @ 500 mA·cm−2, achieving ~84% Faradaic efficiency. Besides electrochemical characterization, the morphology and microstructure of the layered half-cells were analyzed by a combination of high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy-dispersive X-ray spectroscopy. Our results also provide a feasible approach for realizing the low-cost fabrication of large-sized protonic ceramic conducting electrolysis cells (PCECs)..
10. Shohei Nakamura, Atsushi Takagaki, Motonori Watanabe, Kanta Yamada, Masaaki Yoshida, Tatsumi Ishihara, Porous Boron Nitride as a Weak Solid Base Catalyst, ChemCatChem, 10.1002/cctc.202001435, 12, 23, 6033-6039, 2020.12.
11. Jose C. Madrid Madrid, Kotaro Nakamura, Keisuke Inda, Lukas Haneke, Andreas Heckmann, Joop Enno Frerichs, Michael Ryan Hansen, Tobias Placke, Martin Winter, Motonori Watanabe, Atsushi Takagaki, Taner Akbay, Tatsumi Ishihara, Hexafluorophosphate-Bis(trifluoromethanesulfonyl)imide anion co-intercalation for increased performance of dual-carbon battery using mixed salt electrolyte, Journal of Power Sources, 10.1016/j.jpowsour.2020.229084, 479, 229084-229084, 2020.12.
12. Lukas Haneke, Joop Enno Frerichs, Andreas Heckmann, Michael M. Lerner, Taner Akbay, Tatsumi Ishihara, Michael Ryan Hansen, Martin Winter, Tobias Placke, Editors’ Choice—Mechanistic Elucidation of Anion Intercalation into Graphite from Binary-Mixed Highly Concentrated Electrolytes via Complementary 19F MAS NMR and XRD Studies, Journal of The Electrochemical Society, 10.1149/1945-7111/abc437, 167, 14, 140526-140526, 2020.11.
13. Dinh Hoa Nguyen, Tatsumi Ishihara, Distributed peer-to-peer energy trading for residential fuel cell combined heat and power systems, Electrical Power and Energy Systems, 10.1016/j.ijepes.2020.106533, 125, 106533, 2021.02.
14. Yoonyoung Kim, Motonori Watanabe, Junko Matsuda, Jun Tae Song, Atsushi Takagaki, Aleksandar Staykov, Tatsumi Ishihara, Tensile strain for band engineering of SrTiO3 for increasing photocatalytic activity to water splitting, Applied Catalysis B: Environmental, 10.1016/j.apcatb.2020.119292, 278, 119292-119292, 2020.12, SrTiO3 is well-known highly active photocatalyst with high energy conversion efficiency. In this study, we investigated the formation of oxygen vacancy by using the chemo-mechanical effect that occurs the difference of thermal expansion coefficient between metal and metal oxide connecting at high temperature. Au dispersion on SrTiO3 followed by sintering treatment were studied for introduction of chemo-mechanical effects because of a different thermal expansion coefficient; the introduced chemo-mechanical strain generated oxygen vacancy in the lattice structure of SrTiO3. Thus induced chemo-mechanical effect shows change in electronic band structure resulting in narrowing band gap with increasing Au content. Since photoluminescence was significantly decreased by sintering treatment on Au dispersion, the introduced oxygen vacancy may work as a charge separation and adsorption site in water splitting. Therefore, the photocatalytic activity was much increased by sintering treatment of Au dispersed SrTiO3..
15. Qing Wang, Kaveh Edalati, Ikuro Fujita, Motonori Watanabe, Tatsumi Ishihara, Zenji Horita, High-pressure torsion of SiO2 quartz sand: Phase transformation, optical properties, and significance in geology, Journal of the American Ceramic Society, 10.1111/jace.17362, 103, 11, 6594-6602, 2020.11.
16. Ikuro Fujita, Parisa Edalati, Qing Wang, Motonori Watanabe, Makoto Arita, Shinji Munetoh, Tatsumi Ishihara, Kaveh Edalati, Novel black bismuth oxide (Bi2O3) with enhanced photocurrent generation, produced by high-pressure torsion straining, Scripta Materialia, 10.1016/j.scriptamat.2020.06.052, 187, 366-370, 2020.10.
17. Bin Yang, Wei Deng, Limin Guo, Tatsumi Ishihara, Copper-ceria solid solution with improved catalytic activity for hydrogenation of CO2 to CH3OH, Chinese Journal of Catalysis, 10.1016/S1872-2067(20)63605-1, 41, 9, 1348-1359, 2020.09.
18. Songmei Sun, Qi An, Motonori Watanabe, Junfang Cheng, Hack Ho Kim, Taner Akbay, Atsushi Takagaki, Tatsumi Ishihara, Highly correlation of CO2 reduction selectivity and surface electron Accumulation: A case study of Au-MoS2 and Ag-MoS2 catalyst, Applied Catalysis B: Environmental, 10.1016/j.apcatb.2020.118931, 271, 118931-118931, 2020.08.
19. Shushu Huang, Wei Deng, Long Zhang, Dengyao Yang, Qiang Gao, Zhengfang Tian, Limin Guo, Tatsumi Ishihara, Adsorptive properties in toluene removal over hierarchical zeolites, Microporous and Mesoporous Materials, 10.1016/j.micromeso.2020.110204, 302, 110204-110204, 2020.08.
20. Yu Wang, Kaisi Liu, Ji Wu, Zhimi Hu, Liang Huang, Jun Zhou, Tatsumi Ishihara, Limin Guo, Unveiling the Effects of Alkali Metal Ions Intercalated in Layered MnO2 for Formaldehyde Catalytic Oxidation, ACS Catalysis, 10.1021/acscatal.0c02310, 10, 17, 10021-10031, 2020.08.
21. Yuta Koganemaru, Yoonyoung Kim, Motonori Watanabe, Atsushi Takagaki, Tatsumi Ishihara, Z-scheme-type conductive-polymer-P3HT/KTa(Zr)O3 heterojunction composites for enhancing the photocatalytic activity of water splitting, Applied Catalysis A, General, 10.1016/j.apcata.2020.117737, 602, 117737-117737, 2020.07.
22. Siman Fang, Atsushi Takagaki, Motonori Watanabe, Jun Tae Song, Tatsumi Ishihara, Scandium and copper co-doping effect on stability and activity to the NO direct decomposition of Ba3Y4O9, Applied Catalysis A, General, 10.1016/j.apcata.2020.117743, 602, 117743-117743, 2020.07.
23. Yuki Honda, Yuka Shinohara, Motonori Watanabe, Tatsumi Ishihara, Hiroshi Fujii, Photo-biohydrogen Production by Photosensitization with Biologically Precipitated Cadmium Sulfide in Hydrogen-Forming Recombinant Escherichia coli, ChemBioChem, 10.1002/cbic.202000383, 21, 23, 3389-3397, 2020.12.
24. Ikuro Fujita, Kaveh Edalati, Qing Wang, Makoto Arita, Motonori Watanabe, Shinji Munetoh, Tatsumi Ishihara, Zenji Horita, High-pressure torsion to induce oxygen vacancies in nanocrystals of magnesium oxide: Enhanced light absorbance, photocatalysis and significance in geology, Materialia, 10.1016/j.mtla.2020.100670, 11, 100670-100670, 2020.06.
25. Nuttavut Kosem, Yuki Honda, Motonori Watanabe, Atsushi Takagaki, Zahra Pourmand Tehrani, Fatima Haydous, Thomas Lippert, Tatsumi Ishihara, Photobiocatalytic H2 evolution of GaN:ZnO and [FeFe]-hydrogenase recombinant Escherichia coli, Catalysis Science & Technology, 10.1039/d0cy00128g, 10, 12, 4042-4052, 2020.06.
26. Min-Kyu Son, Hyunwoong Seo, Motonori Watanabe, Masaharu Shiratanib, Tatsumi Ishihara, Characteristics of crystalline sputtered LaFeO3 thin films as photoelectrochemical water splitting photocathodes, Nanoscale, 10.1039/D0NR01762K, 12, 17, 9653-9660, 2020.05.
27. Xiao-Feng Shen, Motonori Watanabe, Atsushi Takagaki, Jun Tae Song, Tatsumi Ishihara, Pyridyl-Anchored Type BODIPY Sensitizer-TiO2 Photocatalyst for Enhanced Visible Light-Driven Photocatalytic Hydrogen Production, Catalysts, 10.3390/catal10050535, 10, 5, 535-535, 2020.05.
28. Zhe Tan, Tatsumi Ishihara, Effect of Ni-based cathodic layer on intermediate temperature tubular electrolysis cell using LaGaO3 based electrolyte thin film, JPhys Energy, 10.1088/2515-7655/ab6f4b, 2, 2, 024004-024004, 2020.04.
29. Chitiphon Chuaicham, Sekar Karthikeyan, Radheshyam R. Pawar, Yihuang Xiong, Ismaila Dabo, Bunsho Ohtani, Yoonyoung Kim, Jun Tae Song, Tatsumi Ishihara, Keiko Sasaki, Energy-resolved distribution of electron traps for O/S-doped carbon nitrides by reversed doublebeam photoacoustic spectroscopy and the photocatalytic reduction of Cr(VI), Chemical Communications, 10.1039/c9cc09988c, 56, 26, 3793-3796, 2020.04.
30. Siman Fang, Atsushi Takagaki, Motonori Watanabe, Tatsumi Ishihara, The direct decomposition of NO into N2 and O2 over copper doped Ba3Y4O9, Catalysis Science & Technology, 10.1039/D0CY00194E, 10, 8, 2513-2522, 2020.04.
31. Ryutaro Nozu, Eiko Suzuki, Okitoshi Kimura, Nobuaki Onagi, Tatsumi Ishihara, Tetraethylammonium tetrafluoroborate additives for suppressed gas formation and increased cycle stability of dual-ion battery, Electrochimica Acta, 10.1016/j.electacta.2020.135711, 337, 135711-135711, 2020.03.
32. Ryutaro Nozu, Eiko Suzuki, Okitoshi Kimura, Nobuaki Onagi, Tatsumi Ishihara, Dual-ion battery using graphitic carbon and Li4Ti5O12: Suppression of gas formation and increased cyclability, Electrochimica Acta, 10.1016/j.electacta.2019.135238, 332, 135238-135238, 2020.02.
33. Kaveh Edalati, Ryoko Uehiro, Shuhei Takechi, Qing Wang, Makoto Arita, Motonori Watanabe, Tatsumi Ishihara, Zenji Horita, Enhanced photocatalytic hydrogen production on GaN–ZnO oxynitride by introduction of strain-induced nitrogen vacancy complexes, Acta Materialia, 10.1016/j.actamat.2019.12.007, 185, 149-156, 2020.02.
34. Qing Wang, Kaveh Edalati, Yuta Koganemaru, Shohei Nakamura, Motonori Watanabe, Tatsumi Ishihara, Zenji Horita, Photocatalytic hydrogen generation on lowbandgap black zirconia (ZrO2) produced by highpressure torsion, Journal of Materials Chemistry A, 10.1039/C9TA11839J, 8, 3643-3650, 2020.02.
35. Parisa Edalati, Qing Wang, Hadi Razavi-Khosroshahi, Masayoshi Fuji, Tatsumi Ishihara, Kaveh Edalati, Photocatalytic hydrogen evolution on a highentropy oxide, Journal of Materials Chemistry A, 10.1039/C9TA12846H, 8, 3814-3821, 2020.02.
36. Sijun Luo, Aline Fluri, Song Zhang, Xue Liu, Max Döbeli, George F. Harrington, Rong Tu, Daniele Pergolesi, Tatsumi Ishihara, Thomas Lippert, Thickness-dependent microstructural properties of heteroepitaxial (00.1) CuFeO2 thin films on (00.1) sapphire by pulsed laser deposition, Journal of Applied Physics, 10.1063/1.5140451, 127, 6, 065301-065301, 2020.02.
37. Chitiphon Chuaicham, Sekar Karthikeyan, Jun Tae Song, Tatsumi Ishihara, Bunsho Ohtani, Keiko Sasaki, Importance of ZnTiO3 Phase in ZnTi-Mixed Metal Oxide Photocatalysts Derived from Layered Double Hydroxide, ACS Applied Materials & Interfaces, 10.1021/acsami.9b18785, 12, 8, 9169-9180, 2020.02.
38. Ming Li, Hongjun Niu, John Druce, Helena Téllez, Tatsumi Ishihara, John A. Kilner, Hripsime Gasparyan, M ichael J. Pitcher, Wen Xu, J. Felix Shin, Luke M. Daniels, Leanne A. H. Jones, Vin R. Dhanak, Dingyue Hu, Marco Zanella, John B. Claridge, Matthew J. Rosseinsky, A CO2-Tolerant Perovskite Oxide with High Oxide Ion and Electronic Conductivity, Advanced Materials, 10.1002/adma.201905200, 32, 1, 1905200-1905200, 2020.01.
39. Ran Gao, Abhinav C. P. Jain, Shishir Pandya, Yongqi Dong, Yakun Yuan, Hua Zhou, Liv R. Dedon, Vincent Thoréton, Sahar Saremi, Ruijuan Xu, Aileen Luo, Ting Chen, Venkatraman Gopalan, Elif Ertekin, John Kilner, Tatsumi Ishihara, Nicola H. Perry, Dallas R. Trinkle, Lane W. Martin, Designing Optimal Perovskite Structure for High Ionic Conduction, Advanced Materials, 10.1002/adma.201905178, 32, 1, 1905178-1905178, 2020.01.
40. Yoonyoung Kim, Motonori Watanabe, Junko Matsuda, Aleksandar Staykov, Hajime Kusaba, Atsushi Takagaki, Taner Akbay, Tatsumi Ishihara, Chemo-mechanical strain effects on band engineering of the TiO2 photocatalyst for increasing the water splitting activity, Journal of Materials Chemistry A, 10.1039/c9ta11048h, 8, 3, 1335-1346, 2020.01.
41. Yoonyoung Kim, Motonori Watanabe, Atsushi Takagaki, Junko Matsuda, Tatsumi Ishihara, Spark Plasma Sintering Treatment for Introduction of Oxygen Vacancy in Pt Dispersed SrTiO3 for Increasing Photocatalytic Water Splitting Activity, ChemCatChem, 10.1002/cctc.201901549, 11, 24, 6270-6274, 2019.12.
42. ByeongSu Kang, Junko Matsuda, Tatsumi Ishihara, Cu–Fe–Ni nano alloy particles obtained by exsolution from Cu(Ni)Fe2O4 as active anode for SOFCs, Journal of Materials Chemistry A, 10.1039/c9ta09482b, 7, 26105-26115, 2019.12.
43. Tatsumi Ishihara, Yujin Kong, Shintaro Izuka, Atsushi Takagaki, Decomposition of Methanol on Supported Pd-Au Catalyst for Recovery of Unused Waste Heat at Low Temperature, Journal of the Japan Petroleum Institute, 10.1627/jpi.62.296, 62, 6, 296-302, 2019.11.
44. ByeongSu Kang, Atsushi Takagaki, Tatsumi Ishihara, Exsolution of Nano Metal Particle on Anode for Increased Performance at Low Temperature Operation, ECS Transactions, 10.1149/09101.1915ecst, 91, 1, 1915-1922, 2019.09.
45. Tatsumi Ishihara, ByeongSu Kang, Atsushi Takagaki, Double Columnar Interlayer for Increased Cathodic Activity of Intermediate Temperature Solid Oxide Fuel Cells, ECS Transactions, 10.1149/09101.1355ecst, 91, 1, 1355-1362, 2019.09.
46. Kuan-Ting Wu, Junko Matsuda, Atsushi Takagaki, Tatsumi Ishihara, Electrochemical Performance, Microstructure and Chemical Compositions of Cu-Based Nanoparticles Driven By Exsolution of CuFe2O4 in CO2/H2O and H2O Electrolysis, ECS Transactions, 10.1149/09101.2425ecst, 91, 1, 2425-2432, 2019.09.
47. Kaveh Edalati, Ikuro Fujita, Shuhei Takechi, Yuki Nakashima, Kazuki Kumano, Hadi Razavi-Khosroshahi, Makoto Arita, Motonori Watanabe, Xavier Sauvage, Taner Akbay, Tatsumi Ishihara, Masayoshi Fuji, Zenji Horita, Photocatalytic activity of aluminum oxide by oxygen vacancy generation using high-pressure torsion straining, Scripta Materialia, 10.1016/j.scriptamat.2019.08.011, 173, 120-124, 2019.08.
48. Hidehisa Hagiwara, Ittoku Nozawa, Katsuaki Hayakawa, Tatsumi Ishihara, Hydrogen production by photocatalytic water splitting of aqueous hydrogen iodide over Pt/alkali metal tantalates, Sustainable Energy & Fuels, 10.1039/C9SE00355J, 3, 11, 3021-3028, 2019.08.
49. Motonori Watanabe, Kenta Goto, Takaaki Miyazaki, Masahiko Shibahara, Yuan Jay Chang, Tahsin J. Chowe, Tatsumi Ishihara, Electrocatalytic hydrogen production using [FeFe]-hydrogenase mimics based on tetracene derivatives, New Journal of Chemistry, 10.1039/C9NJ02790D, 43, 35, 13810-13815, 2019.08.
50. Tatsumi Ishihara, Siman Fang, Tomoaki Ide, Effects of strain induced by Au dispersion in Ba and Ni doped Y2O3 on direct decomposition of NO, Molecular Catalysis, 10.1016/j.mcat.2019.110488, 475, 110488-110488, 2019.07.
51. Odtsetseg Myagmarjav, Jin Iwatsuki, Nobuyuki Tanaka, Hiroki Noguchi, Yu Kamiji, Ikuo Ioka, Shinji Kubo, Mikihiro Nomura, Tetsuya Yamaki, Shinichi Sawada, Toshinori Tsuru, Masakoto Kanezashi, Xin Yu, Masato Machida, Tatsumi Ishihara, Hiroaki Abekawa, Masahiko Mizuno, Tomoyuki Taguchi, Yasuo Hosono, Yoshiro Kuriki, Makoto Inomata, Keita Miyajima, Yoshiyuki Inagaki, Nariaki Sakaba, Research and development on membrane IS process for hydrogen production using solar heat, International Journal of Hydrogen Energy, 10.1016/j.ijhydene.2018.03.132, 44, 35, 19141-19152, 2019.07.
52. Leire Ruiz-Rubio, Beñat Artetxe, Leyre Pérez-Álvarez, Jagoba Martín-Caballero, Tatsumi Ishihara, Juan M. Gutiérrez-Zorrilla, José Luis Vilas-Vilela, Toward Advanced Functional Systems: Honeycomb-Like Polymeric Surfaces Incorporating Polyoxovanadates with Surface-Appended Copper-Cyclam Complexes, Molecules, 10.3390/molecules24122313, 24, 12, 2313-2313, 2019.06.
53. Songmei Sun, Ji Wu, Motonori Watanabe, Taner Akbay, Tatsumi Ishihara, Single-Electron-Trapped Oxygen Vacancy on Ultrathin WO3·0.33H2O {100} Facets Suppressing Backward Reaction for Promoted H2 Evolution in Pure Water Splitting, The Journal of Physical Chemistry Letters, 10.1021/acs.jpclett.9b01032, 10, 11, 2998-3005, 2019.05.
54. Tatsumi Ishihara, Il-Chan Jang, Shintaro Ida, Preparation of MnO2-Cr2O3 mesoporous oxide and its application for an active and reversible air catalyst for Li-O2 batteries, Electrochimica Acta, 10.1016/j.electacta.2019.05.126, 317, 594-603, 2019.05.
55. Young-Wan Ju, SangWon Lee, ByeongSu Kang, HackHo Kim, Tatsumi Ishihara, Phase transition of doped LaFeO3 anode in reducing atmosphere and their power generation property in intermediate temperature solid oxide fuel cell, International Journal of Hydrogen Energy, 10.1016/j.ijhydene.2019.05.052, 44, 56, 29641-29647, 2019.05.
56. Tsuyohiko Fujigaya, Ryota Kanamori, Shinsuke Hirata, Junichi Morita, Masamichi Matsumoto, Masato Eguchi, Il-Chan Jang, Tatsumi Ishihara, Naotoshi Nakashima, Effect of nitrogen-containing polymer wrapped around carbon nanotubes for Li–O2 battery cathode, Polymer Journal, 10.1038/s41428-019-0207-2, 51, 9, 921-927, 2019.05.
57. Tatsumi Ishihara, Kenji Yokoe, Takayoshi Miyano, Hajime Kusaba, Mesoporous MnCo2O4 spinel oxide for a highly active and stable air electrode for Zn-air rechargeable battery, Electrochimica Acta, 10.1016/j.electacta.2019.01.092, 300, 455-460, 2019.03.
58. Keisuke Awaya, Akihide Takashiba, Takaaki Taniguchi, Michio Koinuma, Tatsumi Ishihara, Shintaro Ida, Photoelectrochemical properties of a wellstructured 1.3 nm-thick pn junction crystal, Chemical Communications, 10.1039/C9CC01039D, 55, 31, 4586-4588, 2019.03.
59. KuanTing Wu, Tatsumi Ishihara, Spinel-based oxide cathode used for high temperature CO2/H2O co-electrolysis, Solid State Ionics, 10.1016/j.ssi.2018.11.008, 329, 46-51, 2019.01.
60. Taner Akbay, John A. Kilner, Tatsumi Ishihara, Colin Atkinson, Explicit Solution To Extract Self-Diffusion and Surface Exchange Coefficients from Isotope Back-Exchange Experiments, Journal of Physical Chemistry C, 10.1021/acs.jpcc.8b10823, 123, 1, 258-264, 2019.01.
61. Shaozhong Li, Limin Guo, Tatsumi Ishihara, Hydrogenation of CO2 to methanol over Cu/AlCeO catalyst, Catalysis Today, 10.1016/j.cattod.2019.01.015, 339, 352-361, 2019.01.
62. Aleksandar Staykov, Shun Fukumori, Kazunari Yoshizawa, Kenta Sato, Tatsumi Ishihara, John Kilner, Interaction of SrO-terminated SrTiO3 surface with oxygen, carbon dioxide, and water, Journal of Materials Chemistry A, 10.1039/C8TA05177A, 6, 45, 22662-22672, 2018.12.
63. ByeongSu Kang, Atsushi Inoishi, Atsushi Takagaki, Tatsumi Ishihara, Pr2Ni0.71Cu0.24Ga0.05O4-Sm0.2Ce0.8O1.9 composite film as active cathodic layer for intermediate temperature solid oxide fuel cells, Solid State Ionics, 10.1016/j.ssi.2018.10.027, 327, 59-63, 2018.12.
64. A.M.K. Bahrain, Tatsumi Ishihara, Enhanced electrochemical performance of aluminum and cobalt doped La0.5Sr0.5MnO3 composite oxide anode for direct C3H8 oxidation SOFC, AIP Conference Proceedings, 10.1063/1.5080852, 2045, 020039-1-020039-8, 2018.12.
65. Motonori Watanabe, Songmei Sun, Tatsumi Ishihara, Takuya Kamimura, Masato Nishimura, Fumito Tani, Visible Light-Driven Dye-Sensitized Photocatalytic Hydrogen Production by Porphyrin and its Cyclic Dimer and Trimer: Effect of Multi-Pyridyl-Anchoring Groups on Photocatalytic Activity and Stability, ACS Applied Energy Materials, 10.1021/acsaem.8b01113, 1, 11, 6072-6081, 2018.10.
66. Yu Wang, Wei Deng, Yifu Wang, Limin Guo, Tatsumi Ishihara, A comparative study of the catalytic oxidation of chlorobenzene and toluene over Ce-Mn oxides, Molecular Catalysis, 459, 61-70, 2018.09.
67. Ji Wu, Kotaro Fujii, Masatomo Yashima, Aleksandar Staykov, Taner Akbay, Tatsumi Ishihara and John A. Kilner, A systematic evaluation of the role of lanthanide elements in functional complex oxides; implications for energy conversion devices, Journal of Materials Chemistry A, 10.1039/c8ta01191e, 2018.05.
68. Songmei Sun, Motonori Watanabe, Ji Wu, Qi An, and Tatsumi Ishihara, Ultrathin WO3·0.33H2O Nanotubes for CO2 Photoreduction to Acetate with High Selectivity
, Journal of the American Chemical Society, 140, 6474-6482, 2018.04, Artificial photosynthesis from CO2 reduction is severely hampered by the kinetically challenging multi-electron reaction process. Oxygen vacancies (Vo) with abundant localized electrons have great potential to overcome this limitation. However, surface Vo usually have low concentrations and are easily oxidized, causing them to lose their activities. For practical application of CO2 photoreduction, fabricating and enhancing the stability of Vo on semiconductors is indispensable. Here we report the first synthesis of ultrathin WO3·0.33H2O nanotubes with a large amount of exposed surface Vo sites, which can realize excellent and stable CO2 photoreduction to CH3COOH in pure water under solar light. The selectivity for acetum generation is up to 85%, with an average productivity of about 9.4 μmol g–1 h–1. More importantly, Vo in the catalyst are sustainable, and their concentration was not decreased even after 60 h of reaction. Quantum chemical calculations and in situ DRIFT studies revealed that the main reaction pathway might be CO2 → •COOH → (COOH)2 → CH3COOH..
69. T. Ishihara, L.M.Guo, T.Miyano, Y.Inoishi, K.Kaneko and S.Ida, Mesoporous La0.6Ca0.4CoO3 perovskites with large surface areas as stable air electrodes for rechargeable Zn–air batteries, Journal of Materials Chemistry A, 10.1039/C8TA00426A, 6, 7686-7692, 2018.03, LaCoO3系ペロブスカイトは優れたZn-空気電池の空気極触媒になることが分かっていたが、表面積が小さく、繰り返し特性が課題であった。そこで、メソ構造を有する酸化物の合成を検討し、SiO2をテンプレートに用いることで、表面積が200m2/gを超えるLaCoO3系ペロブスカイトが合成できるとともに、合成したペロブスカイトが、酸素のORR/OERに優れた活性と繰り返し特性を示すことを明らかにした。また劣化機構についても、炭素バインダーの酸化で生成したCO2とKOHの反応物のKHCO3の析出であることを示した。.
70. Wachirapun Punkrawee, Azusa Yamanaka, Junko Matsuda, Yukiko Mitoma, Noriko Nishiyama, Tatsumi Ishihara, Pt‐Rh/TiO2/activated carbon as highly active and stable HI decomposition catalyst for hydrogen production in sulfur‐iodine (SI) process, International Journal of Energy Research, 42, 7, 2494-2506, 2018.03.
71. Wachirapun Punkrawee, Azusa Yamanaka, Junko Matsuda, Yukiko Mitoma, Noriko Nishiyama, Tatsumi Ishihara, Pt-Ce0.9Cu0.1O2/activated carbon as highly active and stable HI decomposition catalyst, International Journal of Energy Research, 42, 3, 1088-1097, 2018.02.
72. Lin Liu, Tatsumi Ishihara, Reduction mechanism of selective NO reduction on Pd-NiO/(Y0.99Ba0.01)2O3 catalyst, Applied Catalysis A: General, 550, 90-97, 2018.01.
73. Zhe Tan, Tatsumi Ishihara, Reversible Operation of Tubular Type Solid Oxide Fuel Cells Using LaGaO3 Electrolyte Porous Layer on Dense Film Prepared by Dip-Coating Method, Journal of The Electrochemical Society, 164, 14 , F1690-F1696, 2017.12.
74. Hidehisa Hagiwara, Ryota Kakigi, Shuhei Takechi, Motonori Watanabe, Satoshi Hinokuma, Shintaro Ida, Tatsumi Ishihara, Effects of preparation condition on the photocatalytic activity of porphyrin-modified GaN:ZnO for water splitting, Surface & Coatings Technology, 324, 601-606, 2017.09.
75. Tatsumi Ishihara, Solid Oxide Reversible Cells (SORCs) Using LaGaO3-Based Oxide Electrolyte and Oxide Fuel Electrode, AIP Conference Proceedings, 1877, 020001-1-020001-6, 2017.09.
76. Motonori Watanabe, Yuki Honda, Hidehisa Hagiwara, Tatsumi Ishihara, [FeFe]-Hydrogenase and its organic molecule mimics—Artificial and bioengineering application for hydrogenproduction, Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 33, 1-26, 2017.09.
77. Namhoon Kim, Emily M. Turner, Yoonyoung Kim, Shintaro Ida, Hidehisa Hagiwara, Tatsumi Ishihara, and Elif Ertekin, Two-Dimensional TiO2 Nanosheets for Photo and Electro-Chemical Oxidation of Water: Predictions of Optimal Dopant Species from First-Principles, The Journal of Physical Chemistry C, 121, 35, 19201-19208, 2017.08, 本研究ではRhを単原子で分散したTiO2ナノシートの合成に成功し、水の光分解においてH2の発生サイトの反応機構のついての量子計算結果と実験から検証を行ったものである。種々のドーパントの影響を検討し、Rh上ではH2OがHに解離したのちの再結合が最も行われにくいことから、Rh上で最も水の光分解反応が進みやすく、Rhが助触媒として活性の高くなることを明確にした。.
78. Sivaprakash Sengodan, Young-Wan Ju, Ohhun Kwon, Areum Jun, Hu Young Jeong, Tatsumi Ishihara, Jeeyoung Shin, and Guntae Kim, Self-Decorated MnO Nanoparticles on Double Perovskite Solid Oxide Fuel Cell Anode by in Situ Exsolution, ACS Sustainable Chemistry & Engineering, 5, 10, 9207-9213, 2017.08.
79. Yu-Ming Chen, Tai-Nan Lin, Ming-Wei Liao, Hong-Yi Kuo, Wei-Xin Kao, Sheng-Fu Yang, Kuan-Ting Wu, T. Ishihara, Applications of the Glycine Nitrate Combustion Method for Powder Synthesis on the LSGM-based Electrolyte-supported Solid Oxide Fuel Cells, ECS Transactions (15th International Symposium on Solid Oxide Fuel Cells (SOFC-XV)), 78, 1, 773-781, 2017.07.
80. T. Ishihara, A. M. K. Bahrain, K.T. Wu, Anodic Performance of La0.5Sr0.5Mn0.9Al0.1O3 Perovskite Oxide for Solid Oxide Fuel Cells using Dry C3H8 Fuel, ECS Transactions (15th International Symposium on Solid Oxide Fuel Cells (SOFC-XV)), 78, 1, 2511-2518, 2017.07.
81. Lin Liu, Kohei Murakami, Shintaro Ida, Tatsumi Ishihara, Selective reduction of NOx by C3H6 over Pd–NiO/(Y0.99Ba0.01)2O3 under oxygen excess conditions, Catalysis Communications, 100, 5-9, 2017.06.
82. Yuchi Fan, Shintaro Ida, Aleksandar Tsekov Staykov, Taner Akbay, Hidehisa Hagiwara, Junko Matsuda, K. Kaneko, Tatsumi Ishihara, Ni-Fe Nitride Nanoplates on Nitrogen-Doped Graphene as a Synergistic Catalyst for Reversible Oxygen Evolution Reaction and Rechargeable Zn-Air Battery, Small, 13, 25, 1700099-1-1700099-8, 2017.05, 本研究では従来の研究で見出したNi-Feヒドロゲナーゼを導入した大腸菌において、犠牲剤や無機触媒の最適化を検討したもので、ルチル相とアナタース相の混在するP-25を用いるときに、350nmの光に対する部分量子収率が35%に達することを示している。.
83. Zhe Tan, Tatsumi Ishihara, Sr(La)TiO3 Anode Substrate for Low Ni Diffusion in Sr- and Mg-Doped LaGaO3 Film Prepared with Co-Sintering Method for Intermediate Temperature Tubular Type Solid Oxide Fuel Cells, Journal of The Electrochemical Society, 164, 7, F815-F820, 2017.05.
84. Yuki Honda, Motonori Watanabe, Hidehisa Hagiwara, Shintaro Ida, Tatsumi Ishihara, Inorganic/whole-cell biohybrid photocatalyst for highly efficient hydrogen production from water, Applied Catalysis B: Environmental, 210, 400-406, 2017.04, 本論文では無機触媒と遺伝子組み換えでヒドロゲナーゼを導入した大腸菌をそのまま用いて、メチルビオロゲンで電解を伝えることで、大腸菌から酵素を取り出すことなく、電荷を伝達できることを明らかにしたもので、TiO2を無機触媒に用いることで、水素を発生できることを示した。.
85. K.-T. Wu, H. Téllez, J. Druce, M. Burriel, F. Yang, D. W. McComb, T. Ishihara, J. A. Kilner, S. J. Skinner, Surface chemistry and restructuring in thin-film Lan+1NinO3n+1 (n = 1, 2 and 3) Ruddlesden–Popper oxides, Journal of Materials Chemistry A, 5, 19, 9003-9013, 2017.04, Lan+1NinO3n+1 (n = 1, 2 および 3)の薄膜作成における表面化学に関して検討した。いずれの組成のNi系ルドルスデンポッパード構造酸化物は酸素解離電極触媒として高活性な酸化物である。本研究では低エネルギー散乱装置を用いて、最外原子層の組成を検討した。Lan+1NinO3n+1 (n = 1, 2 および 3)の製膜直後ではNiに富む組成もあったが、すべての組成で、ポストアニールを行うとSrが表面濃縮した。そこで、表面は激しく再構築されることを示した。.
86. Hidehisa Hagiwara, Motonori Watanabe, Shintaro Ida, Tatsumi Ishihara, Overall Water Splitting on Dye-modified Inorganic Semiconductor Photocatalysts, Journal of the Japan Petroleum Institute, 60, 1, 10-18, 2017.03.
87. Shintaro Ida, Kara Kearney, Takamitsu Futagami, Hidehisa Hagiwara, Takaaki Sakai, Motonori Watanabe, Angus Rockett, Tatsumi Ishihara, Photoelectrochemical H2 evolution using TiO2-coated CaFe2O4 without an external applied bias under visible light irradiation at 470 nm based on device modeling, Sustainable Energy & Fuels, 1, 2, 280-287, 2017.03.
88. Takaaki Sakai, Junji Hyodo, Masako Ogushi, Atsushi Inoishi, Shintaro Ida, Tatsumi Ishihara, Evaluation of isotope diffusion coefficient and surface exchange coefficient of ScSZ series oxide by oxygen isotope exchange method, Solid State Ionics, 301, 156-162, 2017.02.
89. Donghwi Jeong, Areum Jun, Young-Wan Ju, Junji Hyodo, Jeeyoung Shin, Tatsumi Ishihara, Tak-Hyoung Lim, Guntae Kim, Structural, Electrical, and Electrochemical Characteristics of LnBa0.5Sr0.5Co1.5Fe0.5O5+δ (Ln=Pr, Sm, Gd) as Cathode Materials in Intermediate-Temperature Solid Oxide Fuel Cells, Energy Technology, 5, 1337-1343, 2017.02.
90. Audi Majdan Kamarul Bahrain, Shintaro Ida, Tatsumi Ishihara, Al-doped La0.5Sr0.5MnO3 as oxide anode for solid oxide fuel cells using dry C3H8 fuel, Journal of Solid State Electrochem, 21, 1, 161-170, 2017.01.
91. Tatsumi Ishihara, Shijing Wang, Kuan-Ting Wu, Highly active oxide cathode of La(Sr)Fe(Mn)O3 for intermediate temperature CO2 and CO2-H2O co-electrolysis using LSGM electrolyte, Solid State Ionics, 299, 60-63, 2017.01.
92. Hackho Kim, Shintaro Ida, Young-Wan Ju, Junko Matsuda, Guntae Kim, Tatsumi Ishihara, Mixing effects of Cr2O3–PrBaMn2O5 for increased redox cycling properties of Fe powder for a solid-oxide Fe–air rechargeable battery, Journal of Materials Chemistry A, 5, 364-371, 2017.01, 1.
93. Jinda Yeyongchaiwat, Hiroshige Matsumoto, Tatsumi Ishihara, Oxidative reforming of propane with oxygen permeating membrane reactor using Pr2Ni0.75Cu0.25Ga0.05O4 perovskite related mixed conductor, Solid State Ionics, 301, 23-27, 2017.01.
94. Soamwadee Chaianansutcharit, Young Wan Ju, Shintaro Ida, Tatsumi Ishihara, Ni doped PrSr3Fe3O10-δ Ruddlesden-Popper oxide for active oxygen reduction cathode for solid oxide fuel cell, Electrochimica Acta, 222, 1853-1860, 2016.12.
95. Jungeun Hyun, Pyoung-Chan Lee, Myoung-Jo Jung, Tatsumi Ishihara, A Simple Preparation of Polyaniline-coated Sulfur Composites for use as Cathodes in Li–S Batteries, Electrochemistry, 84, 11, 836-841, 2016.11.
96. Kenji Obata, Keisuke Mizuta, Yuki Obukuro, Go Sakai, Hidehisa Hagiwara, Tatsumi Ishihara, Shigenori Matsushima, CO2 Sensing Properties of Zr-Added Porous CaFe2O4 Powder, Sensors and Materials, 28, 11, 1157-1164, 2016.11.
97. Seiji Miyoshi, Taner Akbay, Takuya Kurihara, Taro Fukuda, Aleksandar Tsekov Staykov, Shintaro Ida, Tatsumi Ishihara, Fast Diffusivity of PF6− Anions in Graphitic Carbon for a Dual-Carbon Rechargeable Battery with Superior Rate Property, The Journal of Physical Chemistry C, 120, 40, 22887-22894, 2016.10, 1.
98. Audi Majdan Kamarul Bahrain, Shintaro Ida, Tatsumi Ishihara, Increased Anodic Performance of La0.5Sr0.5Mn0.9Al0.1O3 by Doping with Co for Solid Oxide Fuel Cells Using Dry C3H8 Fuel, Journal of The Electrochemical Society, 163, 10, F1279-F1287, 2016.09.
99. Yi Song, Parsian K. Mohseni, Seung Hyun Kim,, Jae Cheol Shin, Tatsumi Ishihara, Ilesanmi Adesida, Fellow, IEEE, Xiuling Li, Senior Member, IEEE, Ultra-High Aspect Ratio InP Junctionless FinFETs by a Novel Wet Etching Method, IEEE ELECTRON DEVICE LETTERS, 37, 8, 970-973, 2016.08.
100. Yuki Honda, Hidehisa Hagiwara, Shintaro Ida, Tatsumi Ishihara, Application to Photocatalytic H2 Production of a Whole-Cell Reaction by Recombinant Escherichia coli Cells Expressing [FeFe]-Hydrogenase and Maturases Genes, Angewandte Chemie, International Edition, 55, 28, 8045-8048, 2016.07, 1.
101. Monica Burriel, Helena Téllez, Richard J. Chater, Remi Castaing, Philippe Veber, Mustapha Zaghrioui, Tatsumi Ishihara, John A. Kilner, Jean-Marc Bassat, Influence of Crystal Orientation and Annealing on the Oxygen Diffusion and Surface Exchange of La2NiO4+δ, The Journal of Physical Chemistry C, 120, 32, 17927-17938, 2016.07.
102. Taner Akbay, Aleksandar Tsekov Staykov, John Druce, Helena Tellez, Tatsumi Ishihara, John A. Kilner, The interaction of molecular oxygen on LaO terminated surfaces of La2NiO4, Journal of Materials Chemistry A, 4, 34, 13113-13124, 2016.06, 1.
103. Andreas Limbeck, Ghislain M. Rupp, Markus Kubicek, Helena Téllez, John Druce, Tatsumi Ishihara, John A. Kilner, Jürgen Fleig, Dynamic etching of soluble surface layers with on-line inductively coupled plasma mass spectrometry detection – a novel approach for determination of complex metal oxide surface cation stoichiometry, Journal of Analytical Atomic Spectrometry, 31, 8, 1638-1646, 2016.06.
104. Hadi Razavi-Khosroshahi, Kaveh Edalati, Masashige Hirayama, Hoda Emami, Makoto Arita, Miho Yamauchi, Hidehisa Hagiwara, Shintaro Ida, Tatsumi Ishihara, Etsuo Akiba, Zenji Horita, Masayoshi Fuji, Visible-Light-Driven Photocatalytic Hydrogen Generation on Nanosized TiO2-II Stabilized by High-Pressure Torsion, ACS Catalysis, 6, 8, 5103-5107, 2016.06.
105. Takaaki Sakai, Atsushi Inoishi, Masako Ogushi, Shintaro Ida, Tatsumi Ishihara, Characteristics of Fe-air battery using Y2O3-stabilized-ZrO2 electrolyte with Ni–Fe electrode and Ba0.6La0.4CoO3-δ electrode operated at intermediate temperature, Journal of Energy Storage, 7, 115-120, 2016.06.
106. Kohei Hosoi, Hidehisa Hagiwara, Shintaro Ida, Tatsumi Ishihara, La0.8Sr0.2FeO3−δ as Fuel Electrode for Solid Oxide Reversible Cells Using LaGaO3-Based Oxide Electrolyte, Journal of Physical Chemistry C, 120, 29, 16110-16117, 2016.05.
107. Helena Téllez, John Druce, Tatsumi Ishihara, John A. Kilner, Effects of Microstructure on Surface Segregation: Role of Grain Boundaries, ECS Transactions, 72, 7, 57-69, 2016.05.
108. John Druce, Helena Téllez, Tatsumi Ishihara, John A. Kilner, Surface Composition and Oxygen Exchange Properties of Alkaline Earth-Free Perovskites; LaCo0.6Ni0.4O3, ECS Transactions, 72, 7, 71-80, 2016.05.
109. Motonori Watanabe, Naoki Uemura, Shintaro Ida, Hidehisa Hagiwara, Kenta Goto, Tatsumi Ishihara, 5,5’-alkylsubsituted indigo for solution-processed optoelectronic devices, Tetrahedron, 72, 29, 4280-4287, 2016.05.
110. Seiji Miyoshi, Hiroki Nagano, Taro Fukuda, Takuya Kurihara, Motonori Watanabe, Shintaro Ida, Tatsumi Ishihara, Dual-Carbon Battery Using High Concentration LiPF6 in Dimethyl Carbonate (DMC) Electrolyte, Journal of The Electrochemical Society, 163, 7, A1206-A1213, 2016.04.
111. Tatsumi Ishihara, Toshikazu Mori, Jun Iwata, Hidehisa Hagiwara, Shintaro Ida, Solid Oxide Amperometric CO Sensor Prepared by DC Sputtering, Solid Oxide Amperometric CO Sensor Prepared by DC Sputtering, 28, 4, 271-277, 2016.04.
112. Hidehisa Hagiwara, Kohei Higashi, Motonori Watanabe, Ryota Kakigi, Shintaro Ida, Tatsumi Ishihara, Effect of Porphyrin Molecular Structure on Water Splitting Activity of a KTaO3 Photocatalyst, Catalysts 2016, 6, 3, 42-10, 2016.03.
113. Hack Ho Kim, Atsushi Inoishi, Shintaro Ida, Tatsumi Ishihara, Solid-oxide Fe-air rechargeable battery using Fe-Ce(Mn,Fe)O2 for low temperature operation, Journal of Materials Chemistry A, 4, 15, 5482-5488, 2016.03.
114. Tatsumi Ishihara, Junji Hyodo, Henning Schraknepper, Ken Tominaga, Shintaro Ida, Effects of Pt Dispersion on Electronic and Oxide Ionic Conductivity in Pr1.90Ni0.71Cu0.24Ga0.05O4, Physical Chemistry Chemical Physics, 18, 16, 11125-11131, 2016.03.
115. Tatsumi Ishihara, Jun Iwata, Effect of additives on RuO2(10wt%)La0.6Sr0.4CoO3 anode for increasing sensitivity of solid oxide amperometric CO Sensor, Sensor and Actuators B: Chemical, 223, 535-539, 2016.02.
116. Junji Hyodo, Ken Tominaga, Shintaro Ida, Tatsumi Ishihara, Effects of three-dimensional mechano-chemical tensile strain on fast oxygen diffusion in Au-dispersed Pr1.90Ni0.71Cu0.24Ga0.05O4+δ, Journal of Materials Chemistry A, 4, 10, 3844-3849, 2016.02.
117. Kohei Hosoi, Takaaki Sakai, Shintaro Ida, Tatsumi Ishihara, Ce0.6Mn0.3Fe0.1O2-δ as an Alternative Cathode Material for High Temperature Steam Electrolysis Using LaGaO3-based Oxide Electrolyte, Electrochimica Acta, 194, 473-479, 2016.02.
118. S. Choi, S. Sengodan, S. Park, Y.-W. Ju, J. Kim, Junji Hyodo, H. Y. Jeong, Tatsumi Ishihara, J. Shin, G. Kim, A robust symmetrical electrode with layered perovskite structure for direct hydrocarbon solid oxide fuel cells: PrBa0.8Ca0.2Mn2O5+d, Journal of Materials Chemistry A, 4, 1747-1753, 2016.01.
119. Kongfa Chen, Junji Hyodo, Na Ai, Tatsumi Ishihara, San Ping Jiang, Boron deposition and poisoning of La0.8Sr0.2MnO3 oxygen electrodes of solid oxide electrolysis cells under accelerated operation conditions, International Journal of Hydrogen Energy, 41, 3, 1419-1431, 2016.01.
120. Tatsumi Ishihara, Yu Yan, Takaaki Sakai, Shintaro Ida, Oxide ion conductivity in doped NdBaInO4, Solid State Ionics, 288, 262-265, 2016.01.
121. Aleksandar Staykov, Tellez Lozano Helena, Taner Akbay, John Druce, Tatsumi Ishihara, John Kilner, Oxygen Activation and Dissociation on Transition Metal Free Perovskite Surfaces, Chemistry of Materials, 27, 24, 8273-8281, 2015.11.
122. Young-Wan Ju, Seonyoung Yoo, Limin Guo, Changmin Kim, Atsushi Inoishi, HuYoung Jeong, Jeeyoung Shin, Tatsumi Ishihara, Sung-Dae Yim, Guntae Kim, Honeycomb-Like Perovskite Oxide Electrocatalyst for a Hybrid Li-Air Battery, Journal of The Electrochemical Society, 162, 14, A2651-A2655, 2015.10.
123. Ghislain M. Rupp, Helena Téllez, John Druce, Andreas Limbeck, Tatsumi Ishihara, John Kilner, Jürgen Fleig, Surface chemistry of La0.6Sr0.4CoO3_δ thin films and its impact on the oxygen surface exchange resistance, Journal of Materials Chemistry A, 3, 45, 22759-22769, 2015.10, The surface composition of dense La0.6Sr0.4CoO3−δ (LSC) thin film model electrodes, deposited by pulsed laser deposition at 600 °C on yttria-stabilized zirconia (100) electrolytes, was investigated by low-energy ion scattering (LEIS) and time resolved inductively coupled plasma mass spectrometry (ICP-MS). Results obtained by both methods agree qualitatively and quantitatively and provide a comprehensive picture of the surface composition and cation diffusion kinetics of LSC. The measurements revealed that freshly prepared LSC thin films already show a Sr-rich and Co-poor termination layer (80% Sr surface coverage). This Sr-rich surface layer was proven to be an equilibrium property of LSC as it forms again at elevated temperatures after removal. The kinetics of this surface reconstruction is surprisingly fast (<1 h at 550 °C) and indicates high Sr mobility in LSC. Electrochemical Impedance Spectroscopy (EIS) measurements at 400 °C revealed the detrimental effect of this surface layer on the oxygen surface exchange and suggest that higher Co concentrations in the termination layer facilitate the oxygen exchange reaction..
124. Helena Téllez, John Druce, Allen Hall, Tatsumi Ishihara, John Kilner, Angus Rockett, Low energy ion scattering: surface preparation and analysis of Cu(In,Ga)Se2 for photovoltaic applications, Progress in Photovoltaics: Research and Applications, 23, 10, 1219-1227, 2015.10.
125. Kohei Hosoi, Takaaki Sakai, Shintaro Ida, Tatsumi Ishihara, Effects of Ce0.6Mn0.3Fe0.1O2-δ Interlayer on Electrochemical Properties of Microtubular SOFC Using Doped LaGaO3 Electrolyte, Journal of The Electrochemical Society, 162, 12, F1379-F1383, 2015.09.
126. Motonori Watanabe, Hidehisa Hagiwara, Yudai Ogata, Aleksandar Staykov, Sean R. Bishop, Nicola Helen Perry, Yuan Jay Chang, Shintaro Ida, Keiji Tanaka, Tatsumi Ishihara, Impact of Alkoxy Chain Length on Carbazole-based, Visible Light-driven, Dye Sensitized Photocatalytic Hydrogen Production, Journal of Materials Chemistry A, 3, 43, 21713-21721, 2015.09.
127. Motonori Watanabe, Yasutaka Doi, Hidehisa Hagiwara, Aleksandar Staykov, Shintaro Ida, Taisuke Matsumoto, Teruo Shinmyozu, Tatsumi Ishihara, Synthesis and Investigation of the Effect of Substitution on the Structure, Physical Properties, and Electrochemical Properties of Anthracenodifuran Derivatives, Journal of Organic Chemistry, 80, 18, 9159-9166, 2015.08.
128. Jung Eun Hyun, Pyoung-Chan Lee, Tatsumi Ishihara, Preparation and electrochemical properties of sulfur-polypyrrole composite cathodes for electric vehicle applications, Electrochimica Acta, 176, 887-892, 2015.07.
129. John Druce, Helena Téllez, Tatsumi Ishihara, John A. Kilner, Surface Composition and Oxygen Transport Properties of LSCF: From Bulk Ceramics to Devices, ECS Transactions, 68, 1, 557-567, 2015.07.
130. Kongfa Chen, Wei Bo, Junji Hyodo, Tatsumi Ishihara, San Ping Jiang, Chromium Deposition and Poisoning of LSCF and LSM Oxygen Electrodes of Solid Oxide Electrolysis Cells, ECS Transactions, 68, 1, 793-799, 2015.07.
131. Tai-Nan Lin, Ruey-Yi Lee, Jen-Yuan Kuo, Tatsumi Ishihara, Kohei Hosoi, Fabrication of SmBa0.5Sr0.5Co2O5+δ Cathode Material and Its Application for Sr- and Mg-Doped LaGaO3 Electrolyte-Supported Solid Oxide Fuel Cell, ECS Transactions, 68, 1, 895-901, 2015.07.
132. Tatsumi Ishihara, Atsushi Inoishi, Hackho Kim, Shintaro Ida, Reversible Type Solid Oxide Fuel Cells Using Ni-Fe-CeO2 Based Cermet Fuel Electrode and Applied for Metal-Air Rechargeable Battery, ECS Transactions, 68, 1, 3279-3288, 2015.07.
133. Kohei Hosoi, Takaaki Sakai, Shintaro Ida, Tatsumi Ishihara, Oxygen Nonstoichiometry and Cathodic Property of Ce0.6Mn0.3Fe0.1O2-δ for High Temperature Steam Electrolysis Cell Using LaGaO3-Based Oxide Electrolyte, ECS Transactions, 68, 1, 3315-3322, 2015.07.
134. Areum Jun, Seonyoung Yoo, Young-Wan Ju, Junji Hyodo, Sihyuk Choi, Hu Young Jeong, Jeeyoung Shin, Tatsumi Ishihara, Tak-hyoung Lim, Guntae Kim, Correlation between fast oxygen kinetics and enhanced performance in Fe doped layered perovskite cathode for solid oxide fuel cells, Journal of Materials Chemistry A, 3, 29, 15082-15090, 2015.06.
135. Jang Il Chan, Shintaro Ida, Tatsumi Ishihara, Lithium Depletion and the Rechargeability of Li–O2 Batteries in Ether and Carbonate Electrolytes, ChemElectroChem, 2, 9, 1380-1384, 2015.06.
136. Tatsumi Ishihara, Low temperature solid oxide fuel cells using LaGao3-based oxide electrolyte on metal support, Journal of the Japan Petroleum Institute, 58, 2, 71-78, 2015.05.
137. Tae Ho Shin, Hidehisa Hagiwara, Shintaro Ida, Tatsumi Ishihara, RuO2 nanoparticle-modified (Ce,Mn,Fe)O2/(La,Sr) (Fe,Mn)O3 composite oxide as an active anode for direct hydrocarbon type solid oxide fuel cells, Journal of Power Sources, 289, 138-145, 2015.05.
138. Soamwadee Chaianansutcharit, Kohei Hosoi, Junji Hyodo, Ju Young Wan, Tatsumi Ishihara, Ruddlesden Popper oxides of LnSr3Fe3O10_d (Ln=La, Pr, Nd, Sm, Eu, and Gd) as active cathodes for low temperature solid oxide fuel cells, Journal of Materials Chemistry A, 3, 23, 12357-12366, 2015.05, Ruddlesden Popper type oxides of LnSr3Fe3O10−δ (Ln = La, Pr, Nd, Sm, Eu, and Gd) have been investigated as active cathodes for solid oxide fuel cells (SOFCs). Among the examined LnSr3Fe3O10−δ, it was found that PrSr3Fe3O10−δ shows the highest activity for the cathode reaction. The prepared LnSr3Fe3O10−δ oxides have a tetragonal crystal structure with the space group I4/mmm. With decreasing the ionic size of Ln3+, the unit cell volume and crystallite size decrease. The temperature and PO2 dependences of electrical conductivities indicate the metal-like behaviour and the predominant hole conduction. The thermal expansion coefficient (TEC) values derived from the non-linear expansion curves of LnSr3Fe3O10−δ are reasonably compatible with those of La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM) electrolyte. The catalytic activity as cathodes for H2-SOFCs depended on Ln ions. A high cathodic activity was achieved on PrSr3Fe3O10−δ (PSFO10) and a maximum power density of 0.51 W cm−2 was achieved at 1073 K when 0.3 mm thick LSGM electrolyte was used. The surface exchange coefficient, k, also confirms the high activity for the dissociation of oxygen on PSFO10. Therefore, PrSr3Fe3O10−δ is highly promising as a cathode for low temperature SOFCs..
139. John Druce, Helena Téllez, Tatsumi Ishihara, John A. Kilner, Surface Segregation in Solid Oxide Electrode Materials Occurring at Intermediate Temperatures, 227th ECS Meeting, ECS Transactions, 66, 2, 61-68, 2015.05.
140. Helena Téllez, John Druce, Yanuo Shi, Markus Kubicek, Neil J. Simrick, Jennifer L. M. Rupp, Tatsumi Ishihara, John A. Kilner, Surface Segregation and Inter-Diffusion of Cations and Impurities in Microelectrodes for Solid Oxide Fuel Cells and Electrolyzers, 227th ECS Meeting, ECS Transactions, 66, 2, 69-77, 2015.05.
141. Kuan-Ting Wu, Helena Téllez, John Druce, Mónica Burriel, Tatsumi Ishihara, John A. Kilner, Stephen J. Skinner, Surface Composition of Layered Ruddlesden-Popper Lan+1NinO3n+1 (n = 1, 2 and 3) Epitaxial Films, 227th ECS Meeting, ECS Transactions, 66, 2, 89-93, 2015.05.
142. Tatsumi Ishihara, Kuan-Ting Wu, Shijing Wang, High Temperature CO2 Electrolysis on La(Sr)Fe(Mn)O3 Oxide Cathode by Using LaGaO3 Based Electrolyte, 227th ECS Meeting, ECS Transactions, 66, 2, 197-205, 2015.05.
143. Kohei Hosoi, Jongeun Hong, Takaaki Sakai, Shintaro Ida, Tatsumi Ishihara, Microtubular SOFC using doped LaGaO3 electrolyte film prepared with dip coating method, Journal of the Ceramic Society of Japan, 123 , 4, 182-186, 2015.04.
144. Helena Téllez, John Druce, John A Kilner, Tatsumi Ishihara, Relating surface chemistry and oxygen surface exchange in LnBaCo2O5-δ air electrodes, Faraday Discussions, 182, 145-157, 2015.04.
145. John Druce, Helena Téllez, Tatsumi Ishihara, John A Kilner, Oxygen exchange and transport in dual phase ceramic composite electrodes, Faraday Discussions, 182, 271-288, 2015.04.
146. Takaaki Sakai, Keita Arakawa, Masako Ogushi, Tatsumi Ishihara, Hiroshige Matsumoto, Yuji Okuyama, Atmosphere dependence of anode reaction of intermediate temperature steam electrolysis using perovskite type proton conductor, Journal of Solid State Electrochemistry, 19, 6, 1793-1798, 2015.03.
147. Atsushi Inoishi, Junji Hyodo, Hack-Ho Kim, Takaaki Sakai, Shintaro Ida, Tatsumi Ishihara, Low temperature operation of a solid-oxide Fe–air rechargeable battery using a La0.9Sr0.1Ga0.8Mg0.2O3 oxide ion conductor, Journal of Materials Chemistry A, 3, 16, 8260-8264, 2015.03.
148. Kongfa Chen, Junji Hyodo, Aaron Dodd, Na Ai, Tatsumi Ishihara, Jian Li, San Ping Jiang, Chromium deposition and poisoning of La0.8Sr0.2MnO3 oxygen electrodes of solid oxide electrolysis cells, Faraday Discussions, 182, 457-476, 2015.03.
149. Atsushi Inoishi, Hack-Ho Kim, Takaaki Sakai, Ju Young Wan, Shintaro Ida, Tatsumi Ishihara, Discharge Performance of Solid-State Oxygen Shuttle Metal–Air Battery Using Ca-Stabilized ZrO2 Electrolyte, ChemSusChem, 8, 7, 1264-1269, 2015.02.
150. Tatsumi Ishihara, Intermediate temperature CO2 electrolysis by using La0.9Sr0.1Ga0.8Mg0.2O3 oxide ion conductor, ISIJ International, 55, 2, 381-386, 2015.02.
151. Motonori Watanabe, Yuan Jay Chang, Po-Ting Chou, Aleksandar Staykov, Masahiko Shibahara, Katsuya Sako, Tatsumi Ishihara, Tahsin J. Chow, Synthesis and electronic properties of ferrocene-containing organic dyads, Tetrahedron Letters, 56, 12, 1548-1551, 2015.02.
152. Helena Téllez, John Druce, Jongeun Hong, Tatsumi Ishihara, John A. Kilner, Accurate and Precise Measurement of Oxygen Isotopic Fractions and Diffusion Profiles by Selective Attenuation of Secondary Ions (SASI), Analytical Chemistry, 87, 5, 2907-2915, 2015.02.
153. Atsushi Inoishi, Maki Matsuka, Takaaki Sakai, Young-Wan Ju, Shintaro Ida, Tatsumi Ishihara, Lithium–Air Oxygen Shuttle Battery with a ZrO2-Based Ion-Conducting Oxide Electrolyte, ChemPlusChem, 80, 2, 359-362, 2015.02.
154. Tatsumi Ishihara, Jing Xie, Tae Ho Shin, Young-Wan Ju, Shintaro Ida, John A. Kilner, Bi doped Pr6O11 as fluorite oxide cathode for all-fluorite solid oxide fuel cells, Journal of Power Sources, 275, 167-174, 2015.02.
155. Shijing Wang, Hidekazu Tsuruta, Minoru Asanuma, Tatsumi Ishihara, Ni–Fe–La(Sr)Fe(Mn)O3 as a New Active Cermet Cathode for Intermediate-Temperature CO2 Electrolysis Using a LaGaO3-Based Electrolyte, Advanced Energy Materials, 5, 2, 1401003/1-1401003/10, 2015.01.
156. Kongfa Chen, Junji Hyodo, Kane M. O’Donnell, William Rickard, Tatsumi Ishihara, San Ping Jianga, Effect of Volatile Boron Species on the Electrocatalytic Activity of Cathodes of Solid Oxide Fuel Cells
III. Ba0.5Sr0.5Co0.8Fe0.2O3-δ Electrodes, Journal of The Electrochemical Society, 161, 12, F1163-F1170, 2014.12.
157. Koichiro Harada, Tetsuya Oishi, Seiji Hamamoto, Takuma Kawasaki, Tatsumi Ishihara, Oxygen desorption properties of Pr6O11 doped with Bi and Ce for low temperature particulate matter oxidation, Applied Catalysis A: General, 492, 223-230, 2014.12.
158. Seung Hyun Kim, Parsian K. Mohseni, Yi Song, Tatsumi Ishihara, Xiuling Li, Inverse Metal-Assisted Chemical Etching Produces Smooth High Aspect Ratio InP Nanostructures, Nano Letter, 15, 1, 641-648, 2014.12.
159. Junji Hyodo, Ken Tominaga, Jong-Eun Hong, Shintaro Ida, Tatsumi Ishihara, Effects of Three-Dimensional Strain on Electric Conductivity in Au-Dispersed Pr1.90Ni0.71Cu0.24Ga0.05O4+δ, The Journal of Physical Chemistry C, 119, 1, 5-13, 2014.12.
160. Young-Wan Ju, Junji Hyodo, Atsushi Inoishi, Shintaro Ida, Tatsumi Ishihara, A Dense La(Sr)Fe(Mn)O3-δ Nano-film Anode for Intermediate-Temperature Solid Oxide Fuel Cells, Journal of Materials Chemistry A, 3, 7, 3586-3593, 2014.12.
161. Shintaro Ida, Namhoon Kim, Elif Ertekin, Sakae Takenaka, Tatsumi Ishihara, Photocatalytic Reaction Centers in Two-Dimensional Titanium Oxide Crystals, Journal of the American Chemical Society, 137, 1, 239-244, 2014.12.
162. Takashi Baba, Tomoya Takizawa, Koichiro Harada, Hiroshi Yamada, Tatsumi Ishihara, Akihide Takami, Effect of Pr doping on catalytic properties of oxide ion conductor, Zr–Nd–O, for soot oxidation, Catalysis Today, 251, 2-6, 2014.11.
163. Aleksandar Staykov, Motonori Watanabe, Tatsumi Ishihara, Kazunari Yoshizawa, Photoswitching of Conductance through Salicylidene Methylamine, The Journal of Physical Chemistry C, 118, 47, 27539-27548, 2014.10.
164. Shintaro Ida, Shota Koga, Takeshi Daio, Hidehisa Hagiwara, Tatsumi Ishihara, Direct Imaging of Light Emission Centers in Two-Dimensional Crystals and Their Luminescence and Photocatalytic Propertie, Angewandte Chemie International Edition, 53, 48, 13078-13082, 2014.10.
165. Limin Guo, Shintaro Ida, Takeshi Daio, Hidehisa Hagiwara, Tatsumi Ishihara, In-situ carbonization of soft-template to directly synthesize the crystalline mesoporous metal oxides with high surface area, New Journal of Chemistry, 38, 12, 5846-5855, 2014.09.
166. Seonyoung Yoo, Areum Jun, Young-Wan Ju, Dorj Odkhuu, Junji Hyodo, Hu Young Jeong, Noejung Park, Jeeyoung Shin, Tatsumi Ishihara, Guntae Kim, Development of Double-Perovskite Compounds as Cathode Materials for Low-Temperature Solid Oxide Fuel Cells, Angewandte Chemie International Edition, 53, 48, 13064-13067, 2014.09, A class of double-perovskite compounds display fast oxygen ion diffusion and high catalytic activity toward oxygen reduction while maintaining excellent compatibility with the electrolyte..
167. Eric Wachsman, Tatsumi Ishihara, John Kilner, Low-temperature solid-oxide fuel cells, MRS Bulletin, 39, 09, 773-779, 2014.09.
168. Musa Alaydrus, Mamoru Sakaue, Susan M. Aspera, Triati D. K. Wungu, Nguyen H. Linh, Tran P. T. Linh, Hideaki Kasai, Tatsumi Ishihara, Takahiro Mohri, A DFT+U study of strain-dependent ionic migration in Sm-doped ceria, Journal of the Physical Society of Japan, 83, 9, 094707/1-094707/8, 2014.08.
169. Hidehisa Hagiwara, Motonori Watanabe, Takeshi Daio, Shintaro Ida, Tatsumi Ishihara, Modification Effect of meso-Hexakis(pentafluorophenyl) [26]Hexaphyrin Aggregates on the Photocatalytic Water Splitting, Chemical Communications, 50, 83, 12515-12518, 2014.08.
170. Motonori Watanabe, Tatsumi Ishihara, Crystal structure of (E)-2-cyano-3-(12-methyl-12H-benzo[b]phenothiazin-11-yl)acrylic acid, Acta Crystallographica Section E: Structure Reports Online, E70, o1026-o1027, 2014.08.
171. Atsushi Inoishi, Takaaki Sakai, Young-Wan Ju, Shintaro Ida, Tatsumi Ishihara, Effect of Ni/Fe ratio on the performance and stability of the Fe-air rechargeable battery using a La0.9Sr0.1Ga0.8Mg0.2O3 electrolyte, International Journal of Hydrogen Energy, 39, 36, 21352-21357, 2014.08.
172. Jong-Eun Hong, Jing Xie, Shintaro Ida, Tatsumi Ishihara, Increased Power Density of Solid Oxide Fuel Cells Using LaGaO3 Film Prepared by Screen Printing Method with (Ba,La)CoO3-δ and Pr1.9(Ni,Cu,Ga)O4+δ Composite Oxide Cathode, Journal of The Electrochemical Society, 161, 10, F1118-F1123, 2014.08.
173. Maki Matsuka, Kazuki Shigedomi, Tatsumi Ishihara, Comparative study of propane steam reforming in vanadium based catalytic membrane reactor with nickel-based catalysts, International Journal of Hydrogen Energy, 39, 27, 14792-14799, 2014.07.
174. John Druce, Helena Tellez, Monica Burriel, Matthew Sharp, Lydia Fawcett, Stuart N Cook, David McPhail, Tatsumi Ishihara, Hidde H. Brongersma, John A Kilner, Surface Termination and Subsurface Restructuring of Perovskite-based Solid Oxide Electrode Materials, Energy & Environmental Science, 7, 11, 3593-3599, 2014.07, We study the outer atomic surfaces of a series of perovskite-based ceramics using low energy ion scattering spectroscopy..
175. John Druce, Helena Téllez, Neil Simrick, Tatsumi Ishihara, John Kilner, Surface composition of solid oxide electrode structures by laterally resolved low energy ion scattering (LEIS), International Journal of Hydrogen Energy, 39, 35, 20850-20855, 2014.07.
176. Young-Wan Ju, Junji Hyodo, Atsushi Inoishi, Shintaro Ida, Tetsuya Tohei, Yeong-Gi So, Yuichi Ikuhara, Tatsumi Ishihara, Double Columnar Structure with a Nanogradient Composite for Increased Oxygen Diffusivity and Reduction Activity, Advanced Energy Materials, 4, 17, 1400783/1-1400783/8, 2014.07.
177. Young-Wan Ju, Junji Hyodo, Atsushi Inoishi, Shintaro Ida, Tatsumi Ishihara, Ce(Mn,Fe)O2 dense film deposited on LaGaO3 electrolyte for dense anode of solid oxide fuel cells, International Journal of Hydrogen Energy, 39, 35, 20777-20782, 2014.07.
178. Helena Téllez, John Druce, Young-Wan Ju, John Kilner, Tatsumi Ishihara, Surface chemistry evolution in LnBaCo2O5+δ double perovskites for oxygen electrodes, International journal of hydrogen energy, 39, 35, 20856-20863, 2014.07.
179. Shintaro Ida, Tatsumi Ishihara, Recent Progress in Two-Dimensional Oxide Photocatalysts for Water Splitting, The Journal of Physical Chemistry Letters, 5, 15, 2533-2542, 2014.07.
180. Tran Phan Thuy Linh, Mamoru Sakaue, Susan Meñez Aspera, Musa Alaydrus, Triati Dewi Kencana Wungu, Nguyen Hoang Linh, Hideaki Kasai, Takahiro Mohri, Tatsumi Ishihara, First-principles calculation on oxygen ion migration in alkaline-earth doped La2GeO5, Journal of Physics: Condensed Matter, 26, 25, 255503/1-255503/14, 2014.06.
181. Motonori Watanabe, Hidehisa Hagiwara, Aoi Iribe, Yudai Ogata, Kenta Shiomi, Aleksandar Staykov, Shintaro Ida, Keiji Tanaka, Tatsumi Ishihara, Spacer effects in metal-free organic dyes for visible-light-driven dye-sensitized photocatalytic hydrogen production, Journal of Materials Chemistry A, 2014, 2, 12952-12961, 2014.06.
182. Junji Hyodo, Ken Tominaga, Young Wan Ju, Shintaro Ida, Tatsumi Ishihara, Increased Oxide Ion Diffusivity and Surface Exchange on Pr2NiO4 Base Oxide by Au Dispersion, ECS Transactions, 61, 1, 123-129, 2014.05.
183. Tatsumi Ishihara, Atsushi Inoishi, Shintaro Ida, Reversible solid state Fe-air rechargeable battery using LaGaO3 based oxide ion conducting electrolyte, Materials Science Forum, 783-786, 1680-1685, 2014.05.
184. Il Chan Jang, Shintaro Ida, Tatsumi Ishihara, Li Utilization and Cyclability of Li-O2 Rechargeable Batteries Incorporating a Mesoporous Pd/β-MnO2 Air Electrode, Electrochemistry, 82, 4, 267-272, 2014.04.
185. Atsushi Inoishi, Takaaki Sakai, Young Wan Ju, Shintaro Ida, Tatsumi Ishihara, Improved cycle stability of Fe–air solid state oxide rechargeable battery using LaGaO3-based oxide ion conductor, Journal of Power Sources, 262, 310-315, 2014.04.
186. Il Chan Jang, Shintaro Ida, Tatsumi Ishihara, Surface Coating Layer on Li Metal for Increased Cycle Stability of Li–O2 Batteries, Journal of The Electrochemical Society, 161, 5, A821-A826, 2014.04.
187. Aleksandar Staykov, Yuuki Ooishi, Tatsumi Ishihara, Immobilizing Metal Nanoparticles on Single Wall Nanotubes. Effect of Surface Curvature, The Journal of Physical Chemistry C, 118, 8907-8916, 2014.04.
188. Young-Wan Ju, Areum Jun, Atsushi Inoishi, Shintaro Ida, Tak-hyoung Lim, Guntae Kim, Tatsumi Ishihara, Growth of Thin-Film Layered Perovskite Cathodes by Pulsed Laser Deposition and their Electrochemical Studies in IT-SOFCs, Journal of The Electrochemical Society, 161, 6, F698-F702, 2014.04.
189. Helena Téllez, Ainara Aguadero, John Druce, Mónica Burriel, Sarah Fearn, Tatsumi Ishihara, David S. McPhail, John A. Kilner, New perspectives in the surface analysis of energy materials by combined time-of-flight secondary ion mass spectrometry (ToF-SIMS) and high sensitivity low-energy ion scattering (HS-LEIS), Journal of Analytical Atomic Spectrometry, 29, 8, 1361-1370, 2014.04.
190. Tatsumi Ishihara, Ryota Nakashima, Yuuki Ooishi, Hidehisa Hagiwara, Matsuka Maki, Shintaro Ida, H2O2 synthesis by selective oxidation of H2 over Pd-Au bimetallic nano colloid catalyst under addition of NaBr and H3PO4, Catalysis Today, 248, 35-39, 2014.04.
191. Tatsumi Ishihara, Oxide ion conductivity in defect perovskite, Pr2NiO4 and its application for solid oxide fuel cells, Journal of the Ceramic Society of Japan, 122, 3, 179-186, 2014.03.
192. Jong-Eun Hong, Shintaro Ida, Tatsumi Ishihara, Decreased sintering temperature of anode-supported solid oxide fuel cells with La-doped CeO2 and Sr- and Mg-doped LaGaO3 films by Co addition, Journal of Power Sources, 259, 282-288, 2014.03.
193. John Druce, Neil Simrick, Tatsumi Ishihara, John Kilner, "Imaging" LEIS of micro-patterned solid oxide fuel cell electrodes, Nuclear Instruments and Methods in Physics Research B: Beam Interactions with Materials and Atoms , 332, 261-265, 2014.03.
194. Limin Guo, Shintaro Ida, Takeshi Daio, Tatsumi Ishihara, Direct soft-templating route to crystalline mesoporous transition-metal oxides, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 451, 136-143, 2014.03.
195. Arjun Kumar Thapa, Bill Pandit, Hem Sharma Paudel, Rajesh Thapa, Shintaro Ida, Jacek B. Jasinski, Gamini U. Sumanasekera, Tatsumi Ishihara, Polythiophene Mesoporous Birnessite-MnO2/Pd Cathode Air Electrode for Rechargeable Li-Air Battery
, Electrochimica Acta, 127, 410-415, 2014.02.
196. Shintaro Ida, Akihide Takashiba, Shota Koga, Hidehisa Hagiwara, Tatsumi Ishihara, Potential Gradient and Photocatalytic Activity of an Ultrathin p-n Junction Surface Prepared with Two-Dimensional Semiconducting Nanocrystals
, Journal of the American Chemical Society, 136, 1872-1878, 2014.01.
197. Junji Hyodo, Ken Tominaga, Young-Wan Ju, Shintaro Ida, Tatsumi Ishihara, Electrical conductivity and oxygen diffusivity in Cu- and Ga-doped Pr2NiO4, Solid State Ionics , 256, 5-10, 2014.01.
198. Junji Hyodo, Shintaro Ida, Tatsumi Ishihara, Oxide ionic conductivity in Pr2(Ni, Cu, Ga)O4 + δ–(Ce, Sm)O2–δ laminated film estimated with the Hebb–Wagner method
, Solid State Ionics, 262, 889-892, 2014.01.
199. Limin Guo, Shintaro Ida, Akihide Takashiba, Takeshi Daio, Norio Teramae, Tatsumi Ishihara, Soft-templating method to synthesize crystalline mesoporous α-Fe2O3 films, New Journal of Chemistry, 38, 4, 1392-1395, 2014.01.
200. Jong-Eun Hong, Shintaro Ida, Tatsumi Ishihara, Effects of transition metal addition on sintering and electrical conductivity of La-doped CeO2 as buffer layer for doped LaGaO3 electrolyte film
, Solid State Ionics, 262, 374-377, 2013.12.
201. Adele L. Pacquette, Hidehisa Hagiwara, Tatsumi Ishihara, Andrew A. Gewirth, Fabrication of an oxysulfide of bismuth Bi2O2S and its photocatalytic activity in a Bi2O2S/In2O3 composite, Journal of Photochemistry and Photobiology A: Chemistry, 277, 27-36, 2013.12.
202. Koichiro Harada, Tetsuya Oishi, Seiji Hamamoto, Tatsumi Ishihara, Lattice Oxygen Activity in Pr- and La-Doped CeO2 for Low-Temperature Soot Oxidation, The Journal of Physical Chemistry C, 118, 559-568, 2013.12, Effects of Pr- and La-doped CeO2 on desorption of active lattice oxygen to soot oxidation were studied. Thermogravimetric analysis under N2 flow indicated that, despite the decrease in reducible Ce content, the amount of oxygen deficiency increases with increasing La content (x) to 15 mol % in Ce0.80–xPr0.20LaxO2. In inert atmosphere, the introduction of oxygen vacancies by doping La increased the available lattice oxygen for desorption. In the oxygen isotopic exchange, under 18O2 flow, desorption of oxygen molecules containing lattice oxygen atom (16O) was favored because of Pr and La doping in CeO2. These dopants increase the exchange rate constant between gas-phase and lattice oxygen atoms. The apparent activation energy, derived from an Arrhenius plot, for CeO2, Ce0.80Pr0.20O2, and Ce0.65 Pr0.20La0.15O2 were 311, 230, and 135 kJ/mol, respectively. The values indicated that Pr and La doping causes facile oxygen exchange between the gas phase and the solid. The comparison of the rate constants for 16O18O formation under 18O2 flow and 18O2/16O2 mixture flow showed that lattice oxygen predominantly contributes to the exchange reaction. Surface exchange coefficient (k) and diffusion coefficient (D) were obtained by secondary ion mass spectrometry (SIMS) depth analysis of the oxides after diffusion annealing in 18O2. The values of both k and D increase by doping Pr and La, and the surface exchange coefficient value, k, especially increases significantly. Hence, Pr and La doping enhances the oxygen exchange with lattice oxygen, and so high soot oxidation activity at low temperature could be related to the increased contribution of lattice oxygen..
203. Jing Xie, Young Wan Ju, Matsuka Maki, Shintaro Ida, Tatsumi Ishihara, Synergy effects of Pr1.91Ni0.71Cu0.24Ga0.05O4 and Ba0.5La0.5CoO3 composite on cathodic activity for intermediate temperature solid oxide fuel cells
, Journal of Power Sources, 228, 229-236, 2013.11.
204. Arjun Kumar Thapa, Bill Pandit, Rajesh Thapa, Tulashi Luitel, Hem Sharma Paudel, Gamini Sumanasekera, Mahendra K. Sunkara, Nanda Gunawardhana, Tatsumi Ishihara, Masaki Yoshio, Synthesis of mesoporous birnessite-MnO2composite as a cathodeelectrode for lithium battery
, Electrochimica Acta, 116, 118-193, 2013.11.
205. Tatsumi Ishihara, Tae Ho Shin, Shintaro Ida, Effects of Metal Additives on Power Generating Property of Direct Hydrocarbon Type SOFC Using LaGaO3 Electrolyte
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 1217-1223, 2013.10.
206. Mamoru Sakaue, Hideaki Kasai, Tatsumi Ishihara, Computational Studies on Ionic and Electronic Conduction of Rare-Earth-Based Oxides Based on Density Functional Theory
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 2411-2418, 2013.10.
207. Jong-Eun Hong, Jing Xie, Shintaro Ida, Tatsumi Ishihara, (La,Ba)CoO3 and Pr1.9(Ni,Cu,Ga)O4 Composite Oxide as Active Cathode for Intermediate , ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 1793-1799, 2013.10.
208. Tran Phan Thuy Linh, Mamoru Sakaue, Musa Alaydrus, Triati Dewi Kencana Wungu, Susan Meñez Aspera, Hideaki Kasai, Tatsumi Ishihara, Alkaline-earth Doped effect on Oxygen Vacancy Migration in Monoclinic Lanthanum Germanate: First-principles calculation
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 1077-1083, 2013.10.
209. Young Wan Ju, Shintaro Ida, Tatsumi Ishihara, La(Sr)Fe(Mn)O3 Thin Film Anode for Improving Power Generating Property with Enhancing Electric Conductivity and Oxidation Activity
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 1463-1468, 2013.10.
210. Liang Zhao, Junji Hyodo, Tatsumi Ishihara, Kazunari Sassaki, Sean R. Bishop, XRD and Raman Spectroscopy Study of Mn Solubility in Cerium Oxide
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 1607-1612, 2013.10.
211. Kongfa Chen, Junji Hyodo, Ling Zhao, Na Ai, Tatsumi Ishihara, San Ping Jiang, Boron Poisoning of (La, Sr)(Co, Fe)O3 Cathodes of Solid Oxide Fuel Cells, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 1821-1830, 2013.10.
212. Sean R. Bishop, John Druce, John A. Kilner, Tatsumi Ishihara, Kazunari Sasaki, Compensation for Oxygen Exchange Rate Limiting Impurities on a Pr0.1Ce0.9O2-δ SOFC Electrode Material
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 2003-2007, 2013.10.
213. Triati Dewi Kencana Wungu, Mamoru Sakaue, Susan Meñez Aspera, Tran Linh Phan Thuy, Musa Alaydrus, Hideaki Kasai, Tatsumi Ishihara, First Principles Study on the Electronic Structure and Properties of Sr- and Mg-Doped LaGaO3, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 2715-2722, 2013.10.
214. Musa Alaydrus, Mamoru Sakaue, Susan Meñez Aspera, Triati Dewi Kencana Wungu, Tran Linh Phan Thuy, Hideaki Kasai, Tatsumi Ishihara, First-principles Study of the Lattice Strain Effects on the Ionic Migration Barrier of Sm-doped Ceria, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 2733-2739, 2013.10.
215. Susan Meñez Aspera, Mamoru Sakaue, Musa Alaydrus, Triati Dewi Kencana Wungu, Tran Linh Phan Thuy, Hideaki Kasai, Tatsumi Ishihara, Investigations on the Structural and Electronic Properties of Pure and Doped Bulk Pr2NiO4 through First Principles Calculations
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 2753-2762, 2013.10.
216. Shijing Wang, Tatsumi Ishihara, La0.6Sr0.4Fe0.9Mn0.1O3 Oxide Cathode for the High Temperature CO2 Electrolysis Using LSGM Electrolyte
, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 3171-3176, 2013.10.
217. John Druce, John A. Kilner, Tatsumi Ishihara, Relating Electrochemical Performance Measurements and Surface Analyses of Pr2-xLaxNiO4+δ Electrode Materials, ECS Transactions, the 13th International Symposium on Solid Oxide Fuel Cells (SOFC-XIII), 57, 1, 3269-3276, 2013.10.
218. Limin Guo, Hidehisa Hagiwara, Shintaro Ida, Takeshi Daio, Tatsumi Ishihara, One-pot Soft-templating Method to Synthesize Crystalline Mesoporous Tantalum Oxide and Its Photocatalytic Activity for Overall Water Splitting, ACS Applied Materials & Interfaces, 5, 21, 11080-11086, 2013.10.
219. John Druce, Tatsumi Ishihara, John A. Kilner, Surface composition of perovskite-type materials studied by Low Energy Ion Scattering (LEIS)
, Solid State Ionics, org/10.1016/j.ssi.2013.09.010, 262, 893-896, 2013.10.
220. Atsushi Inoishi, Takaaki Sakai, Young Wan Ju, Shintaro Ida, Tatsumi Ishihara, A rechargeable Si–air solid state oxygen shuttle battery incorporating an oxide ion conductor, Journal of Materials Chemistry A, 1, 48, 15212-15215, 2013.10, Herein, we report a new type of Si–air rechargeable battery incorporating an oxide ion conducting electrolyte, based on the oxygen shuttle concept. A cell designed in this manner and employing Ca stabilized ZrO2 exhibited stable charge–discharge over 20 cycles at 1073 K and achieved a discharge capacity of approximately 600 mA h gSi−1..
221. Shijing Wang, Atsushi Inoishi, Jong-eun Hong, Young-wan Ju, Hidehisa Hagiwara, Shintaro Ida, Tatsumi Ishihara, Ni–Fe bimetallic cathodes for intermediate temperature CO2 electrolyzers using a La0.9Sr0.1Ga0.8Mg0.2O3 electrol, Journal of Materials Chemistry A, 1, 40, 12455-12461, 2013.09.
222. Hidehisa Hagiwara, Masakiyo Nagatomo, Chihiro Seto, Shintaro Ida, Tatsumi Ishihara, Dye-modification effects on water splitting activity of GaN:ZnO photocatalyst, Journal of Photochemistry and Photobiology A: Chemistry, 272, 41-48, 2013.09.
223. Jing Xie, Young-Wan Ju, Tatsumi Ishihara, Influence of sulfur impurities on the stability of La0.6Sr0.4Co0.2Fe0.8O3 cathode for solid oxide fuel cells, Solid State Ionics, 249-250, 177-183, 2013.09.
224. Shintaro Ida, Akihide Takashiba, Tatsumi Ishihara, Self-Ordering of Disorderly Arranged 2D Crystal Layers to 3D Regular Arrangement Using a Heat-Induced Chemical Reaction between 2D Crystal Layers, The Journal of Physical Chemistry C, 2013, 117, 44, 23357-23363, 2013.09.
225. Koichiro Harada, Tetsuya Oishi, Seiji Hamamoto, Tatsumi Ishihara, Effect of Dopants Pr and La on the Catalytic Activity of Cerium Oxide for Soot Oxidation, The Bulletin of the Chemical Society of Japan, 86, 8, 963-967, 2013.08.
226. Mohamad Azmi Bustam, Zakaria Man, Saikat Maitra, Tatsumi Ishihara, Electrochemical Performance of Cathode LiVOPO4 Doped with Mo and W, Transactions of the Indian Ceramic Society, 72, 2, 108-112, 2013.08.
227. Chunyu Zhu, Akira Nobuta, Young-Wan Ju, Tatsumi Ishihara, Tomohiro Akiyama, Solution combustion synthesis of Ce0.6Mn0.3Fe0.1O2 for anode of SOFC using LaGaO3-based oxide electrolyte, International Journal of Hydrogen Energy, 38, 30, 13419-13426, 2013.08.
228. Hidehisa Hagiwara, Masakiyo Nagatomo, Chihiro Seto, Shintaro Ida, Tatsumi Ishihara, Dye Modification Effects on TaON for Photocatalytic Hydrogen Production from Water, Catalysts, 3, 3, 614-624, 2013.07.
229. Kongfa Chen, Junji Hyodo, Ling Zhao, Na Ai, Tatsumi Ishihara, San Ping Jiang, Effect of Volatile Boron Species on the Microstructure and Composition of (La,Sr)MnO3 and (La,Sr)(Co,Fe)O3 Cathode Materials of Solid Oxide Fuel Cells, Journal of The Electrochemical Society, 160, 9, 1033-1039, 2013.07.
230. Tran Phan Thuy LINH, Mamoru SAKAUE, Musa ALAYDRUS, Triati Dewi Kencana WUNGU, Susan Men˜ez ASPERA, Hideaki KASAI, Takahiro MOHRI, Tatsumi Ishihara, Electronic and Oxygen Migration Properties of Monoclinic La2GeO5-δ, Journal of the Physical Society of Japan, 82, 9, 084702-1-084702-4, 2013.07.
231. Tatsumi Ishihara, Kohei Shigeta, Yuuki Ooishi, Matsuka Maki, Hidehisa Hagiwara, Shintaro Ida, Effects of fluorinated hydrocarbon addition on H2O2 direct synthesis from H2 and air over an Au–Pd bimetallic catalyst supported on rutile-TiO2, Catalysis Science & Technology, 2013, 3, 11, 2971-2975, 2013.05.
232. Shintaro Ida, Yohei Okamoto, Shota Koga, Hidehisa Hagiwara, Tatsumi Ishihara, Black-colored nitrogen-doped calcium niobium oxide nanosheets and their photocatalytic properties under visible light irradiation, RSC Advances, 3, 29, 11521-11524, 2013.05.
233. Musa Alaydrus, Mamoru Sakaue, Susan M Aspera, Triati D K Wungu, Tran P T Linh, Hideaki Kasai, Tatsumi Ishihara, Takahiro Mohri, A first-principles study on defect association and oxygen ion migration of Sm3+ and Gd3+ co-doped ceria, Journal of Physics: Condensed Matter , 25, 22, 2013.05.
234. Maki Matsuka, Mitoki Higashi, Tatsumi Ishihara, Hydrogen production from methane using vanadium-based catalytic membrane reactors, International Journal of Hydrogen Energy , 38, 16, 6673-6680, 2013.04.
235. Young-Wan Ju, Shintaro Ida, Tatsumi Ishihara, A Ce(Mn,Fe)O2 dense nanofilm as an improved active anode for metal-supported solid oxide fuel cells, RSC Advances, 3, 26, 10508-10515, 2013.04.
236. Jing Xie, Ju Young Wan, Matsuka Maki, Shintaro Ida, Tatsumi Ishihara, Synergy effects of Pr1.91Ni0.71Cu0.24Ga0.05O4 and Ba0.5La0.5CoO3 composite on cathodic activity for intermediate temperature solid oxide fuel cells
, Journal of Power Sources, 228, 229-236, 2013.04.
237. Takaaki Sakai, Kaori Isa, Matsuka Maki, Takeshi Kozai, Yuji Okuyama, Tatsumi Ishihara, Hiroshige Matsumoto, Electrochemical hydrogen pumps using Ba doped LaYbO3 type proton conducting electrolyte., International Journal of Hydrogen Energy, 38, 6842-6847, 2013.04.
238. Atsushi Inoishi, Young-Wan Ju, Shintaro Ida, Tatsumi Ishihara, Mg–air oxygen shuttle batteries using a ZrO2-based oxide ion-conducting electrolyte, Chemical Communications, 49, 41, 4691-4693, 2013.04.
239. Ling Zhao, Junji Hyodo, Kongfa Chen, Na Ai, Sudath Amarasinghe, Tatsumi Ishihara, San Ping Jiang, Effect of Boron Deposition and Poisoning on the Surface Exchange Properties of LSCF Electrode Materials of Solid Oxide Fuel Cells, Journal of The Electrochemical Society, 160, 6, F682-F686, 2013.04.
240. Jing Xie, Young-Wan Ju, Takaaki Sakai, Tatsumi Ishihara, Improvement in stability of La0.4Ba0.6CoO3 cathode by combination with La0.6Sr0.4Co0.2Fe0.8O3 for intermediate temperature-solid oxide fuel cells, Journal of Solid State Electrochemistry, 17, 8, 2251-2258, 2013.04.
241. Atsushi Inoishi, Young-Wan Ju, Shintaro Ida, Tatsumi Ishihara, Oxidation rate of Fe and electrochemical performance of Fe–air solid oxide rechargeable battery using LaGaO3 based oxide ion conductor, RSC Advances, 3, 23, 8820-8825, 2013.03.
242. Naoki Watanabe, Atsushi Inoishi, Toshiharu Ooe, Akira Kawakami, Hiroshi Shigefumi, Tatsumi Ishihara, Effects of fuel velocity in anode channel on power generation property of tubular solid oxide fuel cells using LaGaO3 electrolyte film, Electrochimica Acta, 97, 86-91, 2013.03.
243. Jongeun Hong, Shintaro Ida, Tatsumi Ishihara, Ce(Mn,Fe)O2 as An Effective Interlayer for Intermediate Temperature SOFCs Using Doped LaGaO3 Films Prepared by Screen Printing Method, Journal of the Electrochemical Society, 160, 4, F375-F380, 2013.02.
244. Abul Kalam Md. Lutfor Rahman, Rie Indo, Hidehisa Hagiwara, Tatsumi Ishihara, Direct conversion of ethane to acetic acid over H-ZSM-5 using H2O2 in aqueous phase, Applied Catalysis A: General, 456, 82-87, 2013.02.
245. Il Chan Jang, Yuiko Hidaka, Tatsumi Ishihara, Li metal utilization in lithium air rechargeable batteries, Journal of Power Sources, 244, 606-609, 2013.01.
246. Junji Hyodo, Shintaro Ida, John A Kilner, Tatsumi Ishihara, Electronic and oxide ion conductivity in Pr2Ni0.71Cu0.24Ga0.05O4/Ce0.8Sm0.2O2 laminated film, Solid State Ionics, 230, 16-20, 2013.01.
247. Shintaro Ida, Yohei Okamoto, Hidehisa Hagiwara, Tatsumi Ishihara, Preparation and Photocatalytic Properties of Sr2−xBaxTa3O10−yNz Nanosheets, Catalysts, 3, 1-10, 2013.01.
248. Atsushi Inoishi, Young-Wan Ju, Shintaro Ida, Tatsumi Ishihara, Fe-Air rechargeable battery using oxide ion conducting electrolyte of Y2O3 stabilized ZrO2, Journal of Power Sources, 229, 12-15, 2012.12.
249. Arjun Kumar Thapa, Tae Ho Shin, Shintaro Ida, Gamini U. Sumanasekera, Mahendra K. Sunkara, Tatsumi Ishihara, Gold-Palladium nanoparticles supported by mesoporous β–MnO2 air electrode for rechargeable Li-Air battery, Journal of Power Sources, 220,pp211-pp216, 2012.12.
250. Atsushi Inoishi, Shintaro Ida, Shoichi Uratani, Takayuki Okano, Tatsumi Ishihara, Ni-Fe-Ce(Mn,Fe)O2 Cermet Anode for Rechargeable Fe-Air Battery Using LaGaO3 Oxide Ion Conductor as Electrolyte
, RSC Advances, 3, 9, 3024-3030, 2012.12.
251. Ju Young Wan, Shintaro Ida, Tatsumi Ishihara, Nickel-Iron Anode Substrate for Smart Solid Oxide Fuel Cells with a Self-Protecting Function Against Reoxidation, Fuel Cells, Weinheim, Germany, 12(6), pp1064-pp1069, 2012.11.
252. Shintaro Ida, Yohei Okamoto, Hidehisa Hagiwara, Tatsumi Ishihara, Two-dimensional nanocrystals for photocatalytic hydrogen production from water, Preprints of Symposia-American Chemical Society, Division of Fuel Chemistry, 57(1), pp435-pp436, 2012.11.
253. Seok Jun Kim, Takaaki Sakai, Hiroyuki Oda, Yuji Okuyama, Yumi Mizutani, Junichi Hamagami, Matsuka Maki, Tatsumi Ishihara, Hiroshige Matsumoto, Long-term stability of sulfated hydrous titania-based electrolyte for water electrolysis, Journal of the Solid State Electrochemistry, 16, 11, 3587-3592, 2012.11.
254. Masatomo Yashima, Hiroki Yamada, Sirikanda Nuansaeng, Tatsumi Ishihara, Role of Ga3+ and Cu2+ in the High Interstitial Oxide-Ion Diffusivity of Pr2NiO4-Based Oxides: Design Concept of Interstitial Ion Conductors through the Higher-Valence d10 Dopant and Jahn–Teller Effect, Chemistry of Materials, 24, 21, 4100-4113, 2012.11.
255. Shintaro Ida, Keisuke Yamada, Maki Matsuka, Hidehisa Hagiwara, Tatsumi Ishihara, Photoelectrochemical hydrogen production from water using p-type and n-type oxide semiconductor electrodes, Electrochimica Acta, Volume 82, pp 397–401, 2012.11.
256. Jongeun Hong, Toru Inagaki, Shintaro Ida, Tatsumi Ishihara, Titania-Added Ce0.6La0.4O2-δ for the Buffer Layer of High-Performance Solid Oxide Fuel Cells Using Doped Lanthanum Gallate Electrolyte Film, Journal of the American Ceramics Society, 95, 11, 3588-3596, 2012.11.
257. S M Aspera, M Sakaue, T D K Wungu, M Alaydrus, T P T Linh, H Kasai, M Nakanishi, Tatsumi Ishihara, Analysis of structural and electronic properties of Pr2NiO4 through first-principles calculations, Journal of Physics: Condensed Matter, 24(40), 405504/1-405504/10, 2012.10.
258. Atsushi Inoishi, Shintaro Ida, Shouichi Uratani, Takayuki Okano, Tatsumi Ishihara, High capacity of an Fe-air rechargeable battery using LaGaO3-based oxide ion conductor as an electrolyte, Physical Chemistry Chemical Physics, 14, 37, 12818-12822, 2012.10.
259. Tatsumi Ishihara, Arjun Kumar Thapa,, Yuiko Hidaka, Shintaro Ida, Rechargeable Litium-Air Battery Using Mesoporous Co3O4 Mopdified with Pd for Air Electrode, Electrochemistry, 80(10),pp731-pp733, 2012.10.
260. Tatsumi Ishihara, Hidehisa Hagiwara, Shintaro Ida, Photocatalytic Water Splitting Into H2 and O2 and Charge Separation Mechanism on Dye Modified KTa(Zr)O3, International Conference on Fundamental and Applied Sciences 2012 AIP Conference Proceedings , 1482,pp515-pp518, 2012.10.
261. Tatsumi Ishihara, Shotaro Matsushita, Takaaki Sakai, Hiroshige Matsumoto, Intermediate temperature solid oxide electrolysis cell using LaGaO3-base oxide, Solid State Ionics, Volume 225, pp 77–80, 2012.10.
262. Shintaro Ida, Yohei Okamoto, Matsuka Maki, Hidehisa Hagiwara, Tatsumi Ishihara, Preparation of Tantalum-Based Oxynitride Nanosheets by Exfoliation of a Layered Oxynitride, CsCa2Ta3O10-xNy, and Their Photocatalytic Activity, Journal of the American Chemical Society, 134(38), pp15773-pp15782, 2012.09.
263. Tae Ho Shin, Yohei Okamoto, Shintaro Ida, Tatsumi Ishihara, Self-Recovery of Pd Nanoparticles That Were Dispersed over La(Sr)Fe(Mn)O3 for Intelligent Oxide Anodes of Solid-Oxisde Fuel Cells, Chemistry A European Journal, 18(37), pp11695-pp11702, 2012.09.
264. M. Sakaue, W. T. Cahyanto, W. T. D. Kencana, S. M. Aspera, K. Miwa, H. Kishi,, S. Kunikata, H. Nakanishi, W. A. Dino, H. Kasai, Tatsumi Ishihara, First-principles study on oxygen ion conduction of La2GeO5 based on the density functional theory, Journal of Physics Conference Series, 379, 012012/1-012012/8, 2012.08.
265. Aleksandar Tsekov Staykov, Tomonori Nishimi, Kazunari Yoshizawa, Tatsumi Ishihara, Oxygen Activation on Nanometer-Size Gold Nanoparticles, The Journal of Physical Chemistry C, 116(30),pp15992-pp16000, 2012.08.
266. Naoki Watanabe, Akira Kawakami, Hajime Omura, Takuya Hoshiko, Toshiharu Oe, Tatsumi Ishihara, Investigation of Internal Reforming Reaction at Low Temperature Using Micro Tubular Solid Oxide Fuel Cell, Electrochemistry, 80(8),pp566-pp573, 2012.08.
267. Tatsumi Ishihara, Shotaro Matsusita, Hydrogen-oxygen Generation with Intermediate Temperature Steam Electrolysis Using LaGaO3 Based Perovskite Electrolyte for Recovery of Unused Heat Energy, ISIJ International, vol.52, No.8,pp1384-pp1388, 2012.08.
268. Young-Wan Ju, Jong-Eun Hong, Junji Hyodo, Toru Inagaki, Shintaro Ida, Tatsumi Ishihara, New buffer layer material La(Pr)CrO3 for intermediate temperature solid oxide fuel cell using LaGaO3-based electrolyte film, Journal of Materials Research, Volume 27, Issue 15, pp 1906-1914, 2012.08.
269. Young Wan Ju, Tatsumi Ishihara, High power density solid oxide fuel cells using LaGaO3 perovskite oxide thin film prepared by PLD method
, Solid State Ionics, Ionics for Sustainable World, Proceedings of the Asian Conference , 17-20, pp171-pp179, 2012.07.
270. Junji Hyodo, Hidehisa Hagiwara, Tatsumi Ishihara, Improved oxide ionic conductivity in Pr2Ni0.75Cu0.25Ga0.05O4+δ-Sm0.2Ce0.8O1.9 (PNCG-SDC) layer by layer film
, Solid State Ionics, Ionics for Sustainable World, Proceedings of the Asian Conference, 17-20, pp340-pp349, 2012.07.
271. Takaaki Sakai, Shotaro Matsushita, Junji Hyodo, Yuji Okuyama, Maki Matsuka, Tatsumi Ishihara, Hiroshige Matsumoto, Effect of doped ceria interlayer on cathode performance of the electrochemical cell using proton conducting oxide, Electrochimica Acta, Volume 75, pp 179–184, 2012.07.
272. Y. Kimura, Tatsumi Ishihara, Damage mechanism for high strength steel part frame without diaphragm, WIT Transactions on the Built Environment, 124(High Performance Structures and Materials Ⅵ), 343-352, 2012.06.
273. Takaaki Sakai, Seok-Jun Kim, Satoshi Kajitani, Jun-ichi Hamagami, Hiroyuki Oda, Maki Matsuka, Tatsumi Ishihara, Hiroshige Matsumoto, Proton conduction properties of nano-titania modified by sulfuric acid impregnation, Journal of Solid State Electrochemistry, Volume 16, Issue 6, pp 2055-2059, 2012.06.
274. Hidehisa Hagiwara, Masakiyo Nagatomo, Shintaro Ida, Tatsumi Ishihara, Photocatalytic splitting of water into hydrogen and oxygen on organic dye modified KTa(Zr)O3 catalyst, Energy Procedia, 22, pp53-pp60, 2012.05.
275. Jong-Eun Hong, Toru Inagaki, Tatsumi Ishihara , Preparation of LaGaO3 thin film for intermediate temperature SOFC by screen printing method (I), Ionics, Volume 18, Issue 5, pp433-439, 2012.05.
276. Tatsumi Ishihara, Ken Tominaga, Junji Hyodo, Maki Matsuka, Improved electrical conductivity in Pr2Ni(Cu,Ga)O4 film with nano thickness, International Journal of Hydrogen Energy, Volume 37, Issue 9, pp 8066–8072, 2012.05.
277. Young-Wan Ju, Shintaro Ida, Toru Inagaki, Tatsumi Ishihara, Improved reoxidation tolerance of Ni–Fe metal support for LaGaO3 thin film electrolyte cell, Solid State Ionics, Volume 216, pp 58–63, 2012.05.
278. Naoki Watanabe, Toshiharu Ooe, Yosuke Akagi, Tatsumi Ishihara, Estimation of heat generation rate in solid oxide fuel cell module from single cell performance and module performance based on impedance analysis, International Journal of Hydrogen Energy, Volume 37, Issue 10, pp 8562-8571, 2012.05.
279. Seok-Jun Kim, Takaaki Sakai, Hiroyuki Oda, Jun-ichi Hamagami, Yuji Okuyama, Matsuka Maki, Shinichi Ohta, Youichi Shimizu, Tatsumi Ishihara, Hiroshige Matsumoto, Water Electrolysis Using Water-Absorbing Porous Electrolyte Consisting of a Sulfonated Nanotitania Proton Conductor, Electrochemistry, 80(4), pp246-pp248, 2012.04.
280. Tatsumi Ishihara, Improved sintering and electrical properties of La-doped CeO2 buffer layer for intermediate temperature solid oxide fuel cells using doped LaGaO3 film prepared by screen printing process
, Journal of Solid State Electrochemistry, 2012.04.
281. Shintaro Ida, Arjun Kumar Thapa, Yuiko Hidaka, Yohei Okamoto, Maki Matsuka, Hidehisa Hagiwara, Tatsumi Ishihara, Manganese oxide with a card-house-like structure reassembled from nanosheets for rechargeable Li-air battery, Journal of Power Sources, 203, pp159–164, 2012.04.
282. Susumu Hikazudani, Tatsuya Mochida, Naofumi Matsuo, Katsutoshi Nagaoka, Tatsumi Ishihara, Hisayoshi Kobayashi, Yusaku Takita , Monoatomically dispersed Pd/TiO2 catalyst effective for epoxidation of propylene at ambient temperature in the presence of H2 and O2, Journal of Molecular Catalysis A: Chemical, 358, pp89–98
, 2012.03.
283. Tatsumi Ishihara, Yuji Yokoyama, Tateaki Shimosaka, Futoshi Kozono, Hidehisa Hagiwara, Intercalation of PF-6 Anion into Nano Pore into Graphene Layer for Improved Capacity of Hybrid Capacitor, Nanoscience and Nanotechnology Letters, Vol.4,No.2,pp182-pp184, 2012.02.
284. Naoki Watanabe, Toshiharu Ooe, Tatsumi Ishihara, Design of thermal self supported 700W class, solid oxide fuel cell module using, LSGM thin film micro tubular cells, Journal of Power Sources, Volume 199, pp 117-123
, 2012.02.
285. Chanadda Phawachalotrn, Oravan Sanguanruang, Tatsumi Ishihara, Highly selective amperometric sensors for carbon monoxide detection in exhaust gas, Sensors & Actuators: B, 161, pp635-640, 2012.01.
286. Tatsumi Ishihara , Ryota Nakashima, Yohei Nomura , High H2O2 yield in the direct oxidation of H2 with O2 on mono dispersed Pd–Au nano colloid under pressurized conditions, Catalysis Science & Technology , 2, pp961-968, 2012.01.
287. Takaaki Sakai, Junji Hyodo, Tatsumi Ishihara, Hiroshige Matsumoto, Single-nanosize pulverization of solid oxide by means of a wet planetary-bead-milling , Journal of the Ceramic Society of Japan , Vol.120, No.1397, pp 39-42, 2012.01.
288. Li, Jun; Ishihara, Tatsumi; Yoshizawa, Kazunari, Theoretical Revisit of the Direct Synthesis of H2O2 on Pd and Au-Pd Surfaces: A Comprehensive Mechanistic Study, Journal of Physical Chemistry C , 115(51), pp25359-pp25367, 2011.12.
289. Okamoto, Yohei; Ida, Shintaro; Hyodo, Junji; Hidehisa Hagiwara, Tatsumi Ishihara, Synthesis and Photocatalytic Activity of Rhodium-Doped Calcium Niobate Nanosheets for
Hydrogen Production from a Water / Methanol System without Co-catalyst Loading
, Journal of the American Chemical Society,, 133(45), pp18034-pp18037., 2011.10.
290. Kazuya. Goto, and Tatsumi. Ishihara, Direct Decomposition of NO into N2 and O2 over Ba3Y3.4Sc0.6O9 Catalyst, Applied Catalysis, A: General, 409-410, 66-73., 2011.09.
291. Nanda Gunawardhana, Gum-Jae Park, Nikolay Dimov, Arjun Kumar Thapa, Hiroyoshi Nakamura, Hongyu Wang, Tatsumi Ishihara, Masaki Yoshio , Constructing a novel and safer energy storing system using a graphite cathode and a MoO3 anode, Journal of Power Sources , 196, pp7886– pp7890, 2011.09.
292. Hidehisa Hagiwara, Takanori Inoue, Shintaro Ida and Tatsumi Ishihara, Long-time charge separation in porphyrin/KTa(Zr)O3 as water splitting photocatalyst, Phys. Chem. Chem. Phys, 13, pp18031-pp18037. , 2011.08.
293. Arjun Kumar Thapa, Tatsumi Ishihara, Mesoporous -MnO2/Pd catalyst air electrode for rechargeable lithium–air battery, Journal of Power Sources, 196, pp7016–pp7020, 2011.08.
294. Tatsumi Ishihara, Yuji Yokoyama, Futoshi Kozono, Hidemi Hayashi, Intercalation of PF6− anion into graphitic carbon with nano pore for dual carbon cell with high capacity, Journal of Power Sources, 196, pp6956–pp6959, 2011.08.
295. Tatsumi Ishihara, Sm(Sr)CoO3 Nano Cone Cathode and Ni-Fe Metal Support for High Power Density and Reliability
, ECS Transactions,, 35 (1) pp1919-pp1925, 2011.08.
296. Tatsumi Ishihara, Reoxidation behavior of Ni–Fe bimetallic anode substrate in solid oxide fuel cells using a thin LaGaO3 based film electrolyte
, Journal of Power Sources, 196, pp6062–pp6069, 2011.08.
297. Tatsumi Ishihara, Intermediate temperature steam electrolysis using LaGaO3-based electrolyte, Solid State Ionics, Vol.192, pp642-644, 2011.06.
298. Jun Li, Aleksandar Staykov, Tatsumi Ishihara, and Kazunari Yoshizawa, Theoretical Study of the Decomposition and Hydrogenation of H2O2 on Pd and Au-Pd Surfaces:
Understanding toward High Selectivity of H2O2 Synthesis
, The Journal of Physical Chemistry C, Vol 115, No 15, pp7392-pp7398, 2011.05.
299. Nuansaeng Sirikanda, Hiroshige Matsumoto, Tatsumi Ishihara, Effect of Co doping on oxygen permeation in Sr3Ti2O7 with Ruddlesden-Popper structure, Solid State Ionics , 192, pp599–pp601, 2011.05.
300. Young- Wan Ju, Toru Inagaki, Shintaro Ida, and Tatsumi Ishihara, Sm(Sr)CoO3 Cone Cathode on LaGaO3 Thin Film Electrolyte for with IT-SOFC High Power Density, Journal of The Electrochemical Society, 158 (7)  ppB825-ppB830 , 2011.05.
301. Hikazudani Susumu, Mochida Tatsuya, Yano Kenshiro, Nagaoka Katsutoshi, Ishihara Tatsumi, Takita Yusaku, Mono-atomically dispersed Pd on TiO2 as a catalyst for epoxidation of light olefins at low temperatures in the presence of H2 and O2, Catalysis Communications, 12(15), pp1396-1400, 2011.05.
302. Abul Kalam Md. Lutfor Rahman, Masako Kumashiro, and Tatsumi Ishihara, Direct synthesis of formic acid by partial oxidation of methane on H-ZSM-5 solid acid catalyst, Catalysis Communications , 12, pp1198–pp1200, 2011.04.
303. Akihiro Kawahara, Yousuke Takahashi, Yuji Hirano, Masayoshi Hirano, Tatsumi Ishihara, Importance of pore structure control in porous substrate for high oxygen penetration in
La0.6Sr0.4Ti0.3Fe0.7O3 thin film for CH4 partial oxidation
, Solid State Ionics , 190, pp53–pp59, 2011.04.
304. Tatsumi Ishihara, Kazuya Goto, Direct decomposition of NO over BaO/Y2O3 catalyst, Catalysis Today , 2011.03.
305. Tatsumi Ishihara and Hao Zhong, Effects of Fe addition on the surface reaction of the anode of intermediate temperature solid oxide fuel cells, Scripta Materialia , 65 (2011) pp108–pp111, 2011.03.
306. Tatsumi Ishihara, Hiroyuki Eto, JingWang Yan, Intermediate temperature solid oxide fuel cells using LaGaO3 based oxide film deposited by PLD
method
, International journal of hydrogen energy , 36, 2011, pp1862-pp1867, 2011.02.
307. Kaveh Edalati, Akito Yamamoto, Zenji Horita and Tatsumi Ishihara, High-pressure torsion of pure magnesium: Evolution of mechanical properties, microstructures and hydrogen
storage capacity with equivalent strain
, Scripta Materialia, 64 (2011) pp880–pp883, 2011.01.
308. HIROSHIGE MATSUMOTO, Takayoshi Tanji, Koji Amezawa, Tatsuya Kawada, Yoshiharu Uchimoto, Takaaki Sakai, Maki Matsuka, Tatsumi Ishihara, Nanoprotonics in perovsikte-type oxides: Reversible changes in color and ion conductivity due to nanoionics
phenomenon in platinum-containing perovskite oxide
, Solid State Ionics, 182, pp13–pp18, 2010.12.
309. Tae Ho Shin, Parichatr Vanalabhpatana, and Tatsumi Ishihara, Oxide Composite of Ce(Mn,Fe)O2 and La(Sr)Fe(Mn)O3 for Anode of Intermediate Temperature Solid Oxide Fuel Cells Using LaGaO3 Electrolyte, Journal of The Electrochemical Society, 157 (12) ppB1896-ppB1901 ,2010, 2010.12.
310. Young-Wan Ju, Hiroyuki Eto, Toru Inagaki, Shintaro Ida, and Tatsumi Ishihara, Improvement in Thermal Cycling Durability of SOFCs Using LaGaO3-Based Electrolyte by Inserting Convex Sm0.5Sr0.5CoO3 Interlayer, Electrochemical and Solid-State Letters, 2010, Vol. 13, No. 12, pp. B139–B141, 2010.12.
311. Masatomo Yashima,, Nuansaeng Sirikanda, and Tatsumi Ishihara, Crystal Structure, Diffusion Path, and Oxygen Permeability of a Pr2NiO4-Based Mixed Conductor
(Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ
, J. AM. CHEM. SOC., 2010, 132, pp2385–pp2392, 2010.12.
312. Young-Wan Ju, Hiroyuki Eto, Toru Inagaki, Shintaro Ida, Tatsumi Ishihara, Preparation of Ni–Fe bimetallic porous anode support for solid oxide fuel cells using LaGaO3 based electrolyte film with high power density
, Journal of Power Sources, 195 (2010) pp6294–pp6300, 2010.11.
313. Maki Matsuka , Roger D. Braddock, Hiroshige Matsumoto , Takaaki Sakai , Igor E. Agranovski , Tatsumi Ishihara , Experimental and theoretical studies of hydrogen permeation for doped strontium cerates, Solid State Ionics , 181 (2010) pp1328–pp1335, 2010.11.
314. Takaaki Sakai, Satoshi Kajitani, Seok-Jun Kim, Jun-ichi Hamagami, Hiroyuki Oda, Maki Matsuka, Proton conduction properties of hydrous sulfated nano-titania synthesized by hydrolysis of titanyl sulfate, Solid State Ionics , 181 (2010) pp1746–pp1749, 2010.11.
315. Shintaro Ida, Keisuke Yamada, Takuya Matsunaga, Hidehisa Hagiwara, Yasumichi Matsumoto, and Tatsumi Ishihara , Preparation of p-Type CaFe2O4 Photocathodes for Producing Hydrogen from Water, J. AM. CHEM. SOC, 2010, 132, pp17343–pp17345, 2010.11, CaF2O4を光機能電極とするセルで、無バイアス下で水の完全光分解と、外部への電流の引き出しに成功した。.
316. Takaaki Sakai & Hao Zhong & Hiroyuki Eto & Tatsumi Ishihara, Power-generating property of direct CH4 fueled SOFC using LaGaO3 electrolyte, J Solid State Electrochem , 2010.11.
317. Hidehisa Hagiwara,1 Naoko Ono,1 and Tatsumi Ishihara, Effects of Redox Potential of Metallophthalocyanine Dye on Photocatalytic Activity of KTa(Zr)O3 for Water Splitting
, Chemistry Letters 2010,, Vol.39, pp178-pp179, 2010.10.
318. Akihiro Kawahara, Yousuke Takahashi, Yuji Hirano, Masayoshi Hirano, and Tatsumi Ishihar, High Oxygen Permeation Rate in La0.6Sr0.4Ti0.3Fe0.7O3 Thin Membrane on a Porous Support with Multichannel Structure for CH4 Partial Oxidation
, Ind. Eng. Chem. Res. , 2010, 49, pp5511–pp5516, 2010.10.
319. Tatsumi ISHIHARA, Takao KANNO, Steam Electrolysis Using LaGaO3 Based Perovskite Electrolyte for Recovery of Unused Heat Energy, ISIJ International, Vol.50 2010, No.9, pp1291-pp1295, 2010.09.
320. Tatsumi Ishihara, Tae Ho Shin, Parichatr Vanalabhpatana, Koji Yonemoto, and Maki Matsuka, Ce0.6(Mn0.3Fe0.1)O2 as an Oxidation-Tolerant Ceramic Anode for SOFCs Using LaGaO3-Based Oxide Electrolyte, Electrochemical and Solid-State Letters, 2010, Vol. 13, No. 8, pp. B95–B97, 2010.08.
321. Akihiro Kawahara and Tatsumi Ishihara, Oxygen Permeation Property in Nd Deficient Nd2NiO4 Mixed Oxide Doped with Cu and Ga, Electrochemical and Solid-State Letters, 2010, Vol. 13, No. 7, pp. B76–B78, 2010.07.
322. Arjun Kumar Thapa, Gumjae Park, Hiroyoshi Nakamura, Tatsumi Ishihara, Nariaki Moriyama, Toshihiko Kawamura, Hongyu Wang, Masaki Yoshio , Novel graphite/TiO2 electrochemical cells as a safe electric energy storage system, Electrochimica Acta, 55 (2010) pp7305–pp7309, 5 July 2010, 2010.07.
323. Hidehisa Hagiwara, Kousuke Kumagae, and Tatsumi Ishihara, Effects of Nitrogen Doping on Photocatalytic Water-splitting Activity of Pt/KTa0.92Zr0.08O3 Perovskite Oxide Catalyst, Chemistry Letters, Vol.39, No.5, pp498-pp499, 2010.05.
324. Tatsumi Ishihara, Nitiphong Jirathiwathanakul and Hao Zhong, Intermediate temperature solid oxide electrolysis cell using LaGaO3 based perovskite electrolyte, Energy & Environmental Science, Vol 3, No 5, May 2010, pp665-pp672, 2010.05, LaGaO3を電解質とする水蒸気電解セルが、Ni-Fe系電極を用いることで中温でも良好に作動することを明らかにした。.
325. Takaaki Sakai, Hao Zhong, Hiroyuki Eto, Tatsumi Ishihara, Power-generating property of direct CH4 fueled SOFC using LaGaO3 electrolyte, J Solid State Electrochem, (2010) 14:1777–1780, 2010.05.
326. Arjun Kumar Thapa, Kazuki Saimen, and Tatsumi Ishihara, Pd/MnO2 Air Electrode Catalyst for Rechargeable Lithium/Air Battery, Electrochemical and Solid-State Letters, 13(11) A165-A167, 2010, 2010.05, Li-空気2次電池の電極としてPd/MnO2が良好な性能を示し、繰り返し特性も良好な性能を示すことを見出した。.
327. Hidehisa Hagiwara, Hiroshige Matsumoto, Tatsumi Ishihara, Dye Mixing Effects on Photocatalytic Water Splitting Activity on Dye-Modified KTaO3 Catalyst, Journal of Solar Energy Engineering, , Vol. 132, pp 021201-1/pp 021201-5, 2010.05.
328. Tatsumi Ishihara Hiroyuki Eto JingWang Yan, Intermediate temperature solid oxide fuel cells using LaGaO3 based oxide film deposited by PLD method, International Journal of Hydrogen Energy, pp665–pp672, 2010.04.
329. Tatsumi Ishihara, Phawachalotorn Armonat, Rie Kadowaki and Oravan Sanguanruang, Solid Oxide Amperometric CO Sensor for Monitoring Exhaust Gas from Water Heater, Sensors and Materials,, Vol 22, No 4, (2010), pp183-pp192 , 2010.04.
330. Tatsumi Ishihara, Nitiphong Jirathiwathanakul and Hao Zhong, Intermediate temperature solid oxide electrolysis cell using LaGaO3 based perovskite electrolyte, Energy & Environmental Science, pp665–pp672, 2010.03.
331. Nuansaeng Sirikanda, Hiroshige Matsumoto and Tatsumi Ishihara, Effects of rock-salt layer on electronic and oxide ionic mixed conductivity in strontium titanate, SrO(SrTiO3)n (n = 1, 2, ∞), Solid State Ionics, Vol.181, 11 March 2010, pp315–pp321, 2010.03.
332. Tatsumi ISHIHARA, Nitiphong JIRATHIWATHANAKUL, Hao ZHONG, Intermediate temperature solid oxide electrolysis cell using LaGaO3 based perovskite electrolyte, Energy & Environmental Science, 3, 665-672, 2010.03, LaGaO3を電解質とすることで、中温でも優れた特性を有する電解セルを開発することができた。.
333. Hao Zhong, Tatsumi Ishihara, and Hiroshige Matsumoto, Ni-Fe-LaGaO3 based Alloy Anode Cermet for Direct Hydrocarbon type
Solid Oxide Fuel Cell using LaGaO3 Electrolyte
, Materials Science Forum , Vols. 638-642 (2010) pp 1112-1117, 2010.02.
334. Hiroyuki Eto, Taner Akbay, Jun Akikusa, Gakuji Uozumi, Norihisa Chitose, Toru Inagaki and Tatsumi Ishihara, Development of Intermediate-Temperature Solid Oxide Fuel Cells Using Doped
Lanthanum Gallate Electrolyte
, Key Engineering Materials , Vols. 421-422 (2010) pp 340-343, 2010.02.
335. Maki Matsuka, Takaaki Sakai, Hiroshige Matsumoto, Roger D. Braddock , Igor E. Agranovski , Tatsumi Ishihara, Effects of hydrogen on phase stability of ytterbium doped strontium cerates, Materials Letters , 64 (2010) 833-835 , 2010.02.
336. Hiroyuki Ishikawa, Makiko Enoki, Tatsumi Ishihara, Tomohiro Akiyama, Mechanically activated self-propagating high-temperature synthesis of
La0.9Sr0.1Ga0.8Mg0.2O3−ı as an electrolyte for SOFC
, Journal of Alloys and Compounds, 488 (2010) pp238-pp242, 2010.01.
337. Tatsumi Ishihara, Nuansaeng Sirikanda, Kenichi Nakashima, Shogo Miyoshi, and Hiroshige Matsumoto, Mixed Oxide Ion and Hole Conductivity in Pr2−_Ni0.76−xCu0.24GaxO4+_ Membrane, Journal of The Electrochemical Society, , Vol.157, No 1, ppB141-ppB146, , 2010.01.
338. Tatsumi Ishihara, Nuansaeng Sirikanda, Kenichi Nakashima, Shogo Miyoshi, and Hiroshige Matsumoto, Mixed Oxide Ion and Hole Conductivity in Pr2−_Ni0.76−xCu0.24GaxO4+_ Membrane, Journal of The Electrochemical Society, Vol.157, No 1, ppB141-ppB146, 2010.01.
339. Tatsumi Ishihara, Tetsuya Oishi, Seiji Hamamoto, Praseodymium oxide doped with Bi for diesel soot oxidation at low temperature, Catalysis Communications , 10 (2009) pp1722–pp1724, 2009.10.
340. A.K. Thapa, S. Kazuki, H. Matsumoto and T. Ishihara, Lithium-Air Rechargeable Batteries Using MnO2-Carbon Based Air Electrode, Solid Oxide Fuel Cells , 11(SOFC-XI),Vol.25 No.2, 2009.10.
341. Hao Zhong, Hiroshige Matsumoto, Tatsumi Ishihara, Ni-Fe Cermet As Stable Anode For Direct CH4 type SOFC, Solid Oxide Fuel Cells , 11(SOFC-XI),Vol.25 No.2, pp2161-pp2168, 2009.10.
342. Young-Wan Ju, and Tatsumi Ishihara, High Power SOFC Using LSGM Film on Ni-Fe Porous Bi-metal Substrate, Solid Oxide Fuel Cells , 11(SOFC-XI),Vol.25 No.2,pp719-pp726, 2009.10.
343. Tatsumi Ishihara, Tae Ho Shin, Parichatr Vanalabhpatana, Oxide Composite Anode of Ce0.6Mn0.3Fe0.1O2 and La0.6Sr0.4Fe0.9Mn0.1O3 for Oxidation Tolerant SOFC, Solid Oxide Fuel Cells , 11(SOFC-XI),Vol.25 No.2, pp2229-pp2230, 2009.10.
344. Kazuya GOTO, Hiroshige MATSUMOTO, Tatsumi ISHIHARA, Direct decomposition of NO on BaO/Ba-Y-O catalyst, Top Catal, , Vol.52 pp1776-pp1780, 2009.10.
345. Hidehisa HAGIWARA, Takanori INOUE, Kenji KANEKO, and Tatsumi ISHIHARA, Charge-Transfer Mechanism in Pt/Kta(Zr)O3 Photocatalysts Modified with Porphyrinoids for Water Splitting, Chemistry-A European Journal , Vol.15, No.46, pp12862-pp12870, 2009.10.
346. Takaaki SAKAI, Hiroshige MATSUMOTO, Reiri YAMAMOTO, Takao KUDO, Sachio OKADA, Masato WATANABE, Shin-ichi HASHIMOTO, Hitoshi TAKAMURA, Tatsumi ISHIHARA , Performance of palladium electrode for electrochemical hydrogen pump using strontium-zirconate-based proton conductors, Ionics , No.15 pp665-pp670, 2009.09.
347. Hiromi Matsuhashi, Hideo Nakamura, Tatsumi Ishihara, Shinji Iwamoto, Yuichi Kamiya, Junya Kobayashi, Yoshihiro Kubota, Takashi Yamada, Takeshi Matsuda, Koichi Matsushita, Kazuyuki Nakai, Hiroyasu Nishiguchi, Masaru Ogura, Noriyasu Okazaki, Satoshi Sato, Ken-ichi Shimizu, Tetsuya Shishido, Seiji Yamazoe, Tatsuya Takeguchi, Keiichi Tomishige, Hiromi Yamashita, Miki Niwa, Naonobu Katada, Characterization of sulfated zirconia prepared using reference catalysts and application to several model reactions, Applied CatalysisA:General , 360 (2009) pp89-pp97, 2009.08.
348. Tatsumi Ishihara , Yuko Misumi, Hiroshige Matsumoto, Pore size control for mesoporous titanium hydroxide prepared with mixed template molecules and its fluoride ion-exchange property, Microporous and Mesoporous Materials, , Vol.122, pp87–pp92, 2009.06.
349. Hao ZHONG, Hiroshige MATSUMOTO, and Tatsumi ISHIHARA, Development of Ni-Fe Based Cermet Anode for Direct CH4 Fueled Intermediate Temperature SOFC Using LaGaO3 Electrolyte, Electrochemistry, 77,No.2 (2009) pp155-pp157, 2009.02.
350. Tatsumi ISHIHARA, Hiroyuki ETO, Hao ZHONG, and Hiroshige MATSUMOTO, Intermediate Temperature Solid Oxide Fuel Cells Using LaGaO3 Based Perovskite Oxide for Electrolyte, Electrochemistry, 77,No.2 (2009) pp115-pp122, 2009.02.
351. Hao Zhong, Hiroshige Matsumoto, Akira Toriyama, and Tatsumi Ishihara, Honeycomb-Type Solid Oxide Fuel Cell Using La0.9Sr0.1Ga0.8Mg0.2O3 Electrolyte for High Volumetric Power Density, Journal of The Electrochemical Society , 156(1) B74-B79 , 2009.01.
352. Tatsumi ISHIHARA, Low Temperature Diesel Particulate Matter Oxidation Catalyst, Materials Integration ,  Vol.22 No.01 pp19-pp24 , 2009.01.
353. Hao ZHONG, Hiroshige MATSUMOTO, Tatsumi ISHIHARA, Akira TORIYAMA, Ag Current Collector for Honeycomb Solid Oxide Fuel Cells Using LaGaO3-based Oxide Electrolyte, Journal of Power Sources , 186, pp238-pp243 , 2009.01.
354. Young-Wan Ju, Hiroshige Matsumoto,Tatsumi Ishihara, Toru Inagaki, and Hiroyuki Eto, Preparation of LaGaO3 Based Oxide Thin Film on Porous Ni-Fe Metal Substrate and its SOFC Application, Journal of the Korean Ceramic Society, Vol. 45, No. 12, pp796~pp801, 2008.12.
355. Aleksandar Staykov, Takashi Kamachi, Tatsumi Ishihara, and Kazunari Yoshizawa, Theoretical Study of the Direct Synthesis of H2O2 on Pd and Pd/Au Surfaces, The Journal of Physical Chemistry C , Vol.112, No.49, pp19501-pp19505, 2008.09.
356. Yashima, Masatomo; Enoki, Makiko; Wakita, Takahiro; Ali, Roushown; Matsushita, Yoshitaka; Izumi, Fujio; Ishihara, Tatsumi, Structural disorder and diffusional pathway of oxide ions in a doped Pr2NiO4-based mixed conductor , Journal of the American Chemical Society , 130(9), pp2762-pp2763. , 2008.09.
357. Hideharu Iwakuni, Yusuke Shinmyou, Hiroaki Yano, Kazuya Goto, Hiroshige Matsumoto, and Tatsumi Ishihara, Effects of Added CO2 and H2 on the Direct Decomposition of NO over BaMnO3-Based Perovskite Oxide, Bulletin of the Chemical Society of Japan , Vol. 81, No. 9, pp1175-pp1182 , 2008.09.
358. Hiroyuki Michishita, Yuko Misumi, Daizo Haruta, Tatsuo Masaki, Nagaaki Yamamoto, Hiroshige Matsumoto, and Tatsumi Ishihara , Cathodic Performance of La0.6Sr0.4CoO3 Perovskite Oxide for Platinum-Free Alkaline Water Electrolysis
Cell
, Journal of The Electrochemical Society, , 155(9) B969-B971, 2008.09.
359. Takaaki Sakai, Hiroshige Matsumoto, Takao Kudo, Reiri Yamamoto, Eiki Niwa, Sachio Okada, Shinichi Hashimoto, Kazuya Sakaki, Tatsumi Ishihara, High performance of electroless-plated platinum electrode for electrochemical hydrogen pumps using strontium-zirconate-based proton conductors, Electrochimica Acta , 53 pp8172-pp8177, 2008.08.
360. Zhong, Hao; Matsumoto, Hiroshige; Ishihara, Tatsumi; Toriyama, Akira, Self-supported LaGaO3-based honeycomb-type solid oxide fuel cell with high volumetric power density, Solid State Ionics , 179(27-32), 1474-1477., 2008.07.
361. Hiroshige Matsumoto , Ikuyo Nomura , Sachio Okada , Tatsumi Ishihara, Intermediate-temperature solid oxide fuel cells using perovskite-type oxide based on barium cerate, Solid State Ionics, , 179 pp1486-pp1489, 2008.07.
362. Tatsumi Ishihara, Kenichi Nakashima, Sachio Okada , Makiko Enoki , Hiroshige Matsumoto, Defect chemistry and oxygen permeation property of Pr2Ni0.75Cu0.25O4 oxide doped with Ga, Solid State Ionics, , 179, pp1367-pp1371, 2008.07.
363. Zhonghe Bi, Hiroshige Matsumoto, Tatsumi Ishihara, Solid-state amperometric CH4 sensor using, LaGaO3-based electrolyte, Solid State Ionics,, 179 , pp1641-pp1644, 2008.07.
364. Yohei Nomura, Tatsumi Ishihara, Yuiko Hata, Kotaro Kitawaki, Kenji Kaneko, Hiroshige Matsumoto, Nanocolloidal Pd-Au as Catalyst for the Direct Synthesis of Hydrogen Peroxide from H2 and O2 , Chem Sus Chem , Vol.1 Issue7 , 2008.07.
365. Tatsumi Ishihara, Jingwang Yan, Makiko Enoki, Sachio Okada, Hiroshige Matsumoto, Ni–Fe Alloy-Supported Intermediate Temperature SOFCs Using LaGaO3 Electrolyte Film for Quick Startup, Journal of fuel cell science and technology, Vol.5, 031205-1‐031205-3, 2008.07.
366. Yohei Nomura, Tatsumi Ishihara, Yuiko Hata, Kotaro Kitawaki, Kenji Kaneko, Hiroshige Matsumoto, Nanocolloidal Pd-Au as Catalyst for the Direct Synthesis of Hydrogen Peroxide from H2 and O2, Chem Sus Chem , Vol.1 Issue7 pp619-pp621, 2008.07.
367. T.Ishihara, R.Kadowaki and H.Mataumoto, Amperometric Solid State CO Sensor in Exhaust Gas by Using Solid State Electrolyte, Chemical Sensors, , Vol.24 Supplement B pp130-pp132, 2008.05.
368. Ito, Naoki; Matsumoto, Hiroshige; Kawasaki, Yuya; Okada, Sachio; Ishihara, Tatsumi, Introduction of In or Ga as second dopant to BaZr0.9Y0.1O3-δ to achieve better sinterability, Solid State Ionics, 179(9-10), 324-329, 2008.05.
369. Yuji Yokoyama, Nobuaki Shimosaka, Hiroshige Matsumoto, Masaki Yoshio, and Tatsumi Ishihara, Effects of Supporting Electrolyte on the Storage Capacity of Hybrid Capacitors Using Graphitic and Activated Carbon, Electrochemical and Solid-State Letters, Vol.11, No.5, pp.A72–pp.A75, 2008.05.
370. Ito, Naoki; Matsumoto, Hiroshige; Kawasaki, Yuya; Okada, Sachio; Ishihara, Tatsumi, Introduction of In or Ga as second dopant to BaZr0.9Y0.1O3-δ to achieve better sinterability, Solid State Ionics , (2008), 179(9-10), 324-329. , 2008.05.
371. Ishihara, Tatsumi, Development of highly selective gas sensor for environmental monitoring , Chemical Sensors, 24(Suppl. A), 91-93, 2008.04.
372. Ishihara, Tatsumi, Development of highly selective gas sensor for environmental monitoring, Chemical Sensors, 24(Suppl. A), 91-93. , 2008.04.
373. Tatsumi Ishihara, Yusuke Shinmyo, Kazuya Goto, Noriko Nishiyama, Hideharu Iwakuni, and Hiroshige Matsumoto, NO Decomposition on Ruddlesden‐Popper-Type Oxide,Sr3Fe2O7,Doped with Ba and Zr, Chemistry Letters , Vol.37 No.3 pp318-pp319, 2008.03.
374. Hidehisa Hagiwara, Hiroshige Matsumoto, and Tatsumi Ishihara, Improvement of Photocatalytic Activity of Metal Sulfide by Organic Dye for H2 Formation from Water, Electrochemistry, Vol.76 No.2 pp125-pp127, 2008.02.
375. Hideharu Iwakuni, Yusuke Shinmyou, Hiroshige Matsumoto, and Tatsumi Ishihara, Direct Decomposition of NO into N2 and O2 on SrFe0.7Mg0.3O3 Perovskite Oxides, The Chemical Society of Japan, Vol80 No.10 2007 pp.2039-2046, 2007.10.
376. Hao Zhong, Hiroshige Matsumoto, Tatsumi Ishihara and Akira Toriyama, Honeycomb-type Solid Oxide Fuel Cells Using La0.9Sr0.1Ga0.8Mg0.2O3 Electrolyte, Chemistry Letters, Vol.36 No. 7 p.846-847, 2007.07.
377. Tatsumi Ishihara, Yuiko Hata, Yohei Nomura, Kenji Kaneko, and Hiroshige Matsumoto, Pd–Au Bimetal Supported on Rutile–TiO2 for Selective Synthesis of Hydrogen Peroxide by Oxidation of H2 with O2 under Atmospheric Pressure, Chemistry Letters, Vol. 36 , No. 7 p.878-879, 2007.07.
378. H. Zhon, H. Matsumoto, T. Ishihara, A. Toriyama, Power Generating Performance of Honeycomb-type Solid Oxide Fuel Cell Consisting of LaGaO3 Based
Oxide Electrolyte
, Solid Oxide Fuel Cells 10(SOFC-X)-Part1, 7(1) pp669-675, 2007.06.
379. M. Kawasaki, N. Chitose, J. Akikusa, T. Akbay, H. Eto, T. Inagaki, T. Ishihara, Lanthanum Doped Barium Cobaltite as a Novel Cathode for Intermediate-temperature SOFC Using Lanthanum Gallate Electrolyte, Solid Oxide Fuel Cells 10(SOFC-X)-Part1, 7(1) pp1229-1234, 2007.06.
380. T. Ishihara, J. W. Yan, H. Matsumoto, High Power SOFC using LaGaO3 Based Oxide Electrolyte Film Prepared on Porous Metal Substrate, Solid Oxide Fuel Cells 10(SOFC-X)-Part1, 7(1) pp435-442, 2007.06.
381. S. Awatsu, H. Iwasaki, K. Isono, N. Chitose, G. Uozumi, T. Inagaki, T. Ishihara, Nano-metal Dispersed Anode of Intermediate-temperature SOFC for High Power Density Operation, Solid Oxide Fuel Cells 10(SOFC-X)-Part1, 7(1) pp1583-1589, 2007.06.
382. Hiroshige Matsumoto, Yoshihisa Furuya, Sachio Okada, Takayoshi Tanji, and Tatsumi Ishihara, Effect of Dispersion of Nanosize Platinum Particles on Electrical Conduction properties of Proton-Conducting Oxide SrZr0.9Y0.1O3-α, Electrochemical and Solid-State Letters , 10(4), P11-P13, 2007.04.
383. Hiroshige Matsumoto, Yuya Kawasaki, Naoki Ito, Makiko Enoki, and Tatsumi Ishihara, Relation Between Electrical Conductivity and Chemical stability of BaCeO3-Based Proton Conductors with Different Trivalent Dopants, Electrochemical and Solid-State Letters , 10(4), B77-B80, 2007.04.
384. Tatsumi Ishihara, Muneki Koga, Hiroshige Matsumoto, and Masaki Yoshio, Electrochemical Intercalation of Hexafluorophosphate Anion into Various Carbons for Cathode of Dual-Carbon Rechargeable Battery, Electrochemical and Solid-State Letters, 10(3)A74-A76, 2007.03.
385. Hideharu Iwakuni, Yusuke Shinmyou, Hiroshi Yano, Hiroshige Matsumoto, Tatsumi Ishihara, Direct decomposition of NO into N2 and O2 on BaMnO3-based perovskite oxides, Applied Catalysis B : Environmental , 74,pp299-306, 2007.03.
386. Shogo Miyoshi, tetsuro Furuno, Oravan Sangoanruang, Hiroshige Matsumoto, and Tatsumi Ishihara, Mixed Conductivity and Oxygen Permeability of Doped Pr2NiO4-Based Oxides, Journal of The Electrochemical Society, 154(1)B57-B62, 2007.01.
387. Nitiphong Jirathiwathanakul, Hiroshige Matsumoto, and Tatsumi Ishihara, Intermediate Temperature Steam Electrolysis Using Doped Lanthanum Gallate Solid Electrolyte (2) Effects of CeO2 Interlayer on Activity, Eco-Materials Processing and Design VIII Materials Science Forum , Vols.544-545 pp1005-1008, 2007.01.
388. Hao Zhong, Hiroshige Matsumoto, Tatsumi Ishihara, Akira Toriyama, Development of Honeycomb-type Solid Oxide Fuel Cell Consisting of LaGaO3 Electrolyte, Eco-Materials Processing and Design VIII Materials Science Forum , Vols.544-545 pp969-972, 2007.01.
389. Hidehisa Hagiwara, Hiroshige Matsumoto, Tatsumi Ishihara, Effects of Dye mixing on Photocatalytic Splitting of H2O into H2 and O2 on KTaO3, Eco-Materials Processing and Design VIII Materials Science Forum , Vols.544-545 pp51-54, 2007.01.
390. Tatsumi Ishihara, Satoko Fukui, Makiko Enoki, and Hiroshige Matsumoto, Oxide Anode Derived from Sr-Doped LaMnO3 Perovskite Oxide for SOFCS Using LaGaO3 Electrolyte, Journal of The Electrochemical Society, 153(11)A2085-A2090, 2006.11.
391. T.Ishihara, K. Nishida, H. Nishiguchi, Y. Takita, K. Chaki, A new reforming process based on CH4 decomposition using a hydrogen-permeating membrane reactor, Research on Chemical Intermediates, Volume 32, Numbers 3-4, 2006, pp.253-262, 2006.10.
392. A. Dutta and T. Ishihara, An Amperometric Solid State NO Sensor Using a LaGaO3 Electrolyte for Monitoring Exhaust Gas, Materials and Manufacturing Processes, Vol. 21, pp.225-228, 2006.09.
393. Tatsumi Ishihara, Development of New Fast Oxide Ion Conductor and Application for Intermediate Temperature Solid Oxide Fuel Cells, Bulletin of the Chemical Society Japan, Vol.79 No.8 pp.1155-1166, 2006.08.
394. Tatsumi Ishihara, Development of New Fast Oxide Ion Conductor and Application for Intermediate Temperature Solid Oxide Fuel Cells, Bulletin of the Chemical Society Japan, Vol.79 No.8 pp.1155-1166, 2006.08.
395. Tatsumi Ishihara, Masashi Nakasu, Isamu Yasuda, Hiroshige Matsumoto, Preparation of Si-carbon nanotube composite by decomposition of tetramathylsilane(TMS)and its hydrogen property, Science and Technology of Advanced Materials, 7 ,667-671, 2006.07.
396. Jingwang Yan, Hiroshige Matsumoto, Taner Akbay, Takashi Yamada, Tatsumi Ishihara, Prepartion of LaGaO3-based perovskite oxide film by a pulsed-laser ablation method and application as a solid oxide fuel cell electrolyte, Journal of Power Sources, Vol.157, pp.714-719, 2006.07.
397. J.W.Yan, H.matsumoto and T.Ishihara, Development of intermediate temperature SOFC using LaGaO3 based oxide film, Energy Materials, VOL1 NO2 pp.116-120, 2006.02.
398. Tatsumi ISHIHARA, Masaki ANDO, Makiko ENOKI, Yusaku TAKITA, Oxide ion conductivity in La(Sr)Ga(Fe,Mg)O3 and its application for solid oxide fuel cells, Journal of Alloys and Compounds, 408-412  pp.507-pp.511, 2006.01.
399. Hidehisa Hagiwara, Naoko Ono, Takanori Inoue, Hiroshige Matsumoto, and Tatsumi Ishihara, Dye-Sensitizer Effects on a Pt/Kta(Zr)O3 Catalyst for the photocatalytic Splitting of Water, Angewandte Chemie International Edition, Number 9, 1420-1422, 2006.01.
400. Hiroyuki Ishikawa, Makiko Enoki, Tatsumi Ishihara and Tomohiro Akiyama, Combustion Synthesis of Doped Lanthanum Gallate as an Electrolyte for Solid Oxide Fuel Cells, Materials Transactions, Vol.47, No.1 pp.149-155, 2006.01.
401. Jun Akikusa, Takashi Yamada, Takafumi Kotani, Naoya Murakami, Taner Akbay, Akihiro Hasegawa, Masaharu Yamada, Norikazu Komada, Sin Nakamura, Norihisa Chitose, Katsuya Hirata, Shigeru Sato, Takashi Miyazawa, Makoto Shibata, Kei Hosoi, Futoshi Nishiwaki, To, SOFC Module and System Development by Means Sealless Metallic Separators with Lanthanum Gallate Electrolyte, Journal of The Electrochemical Society, 153(3)A589-A594, 2006.01.
402. Jingwang Yan, Hiroshige Matsumoto, Taner Akbay, Takashi Yamada, Tatsumi Ishihara, Prepartion of LaGaO3-based perovskite oxide film by a pulsed-laser ablation method and application as a solid oxide fuel cell electrolyte, Journal of Power Sources, 157,pp.714-pp.719, 2006.01.
403. Tatsumi Ishihara, Shogo Miyoshi, Tetsuro Furuno, Oravan Sanguanruang,HiroshigeMatsumoto, Mixed Conductivity and oxygen permeability of doped Pr2 NiO4-based oxide, Solid State Ionics, 177,3087-3091, 2006.01.
404. Tatsumi Ishihara, Jingwang Yan, Hiroshige Matsumoto, Extraordinary fast oxide conductivity in La1.61GeO5-δ thin film consisting of nano-size grain, Solid State Ionics, 177 , 1733-1736, 2006.01.
405. Tatsumi Ishihara, Junichi tabuchi, Shinji Ishikawa, Jingwang Yan, Makiko Enoki, Hiroshige Matsumoto, Recent progress in LaGaO3 based solid electrolyte for intermediate temperature SOFCs, Solid State Ionics, 177 ,1949-1953, 2006.01.
406. Makiko Enoki, Jingwang Yan, Hiroshige Matsumoto, Tatsumi Ishihara, High oxide ion conductivity in Fe and Mg doped LaGaO3 as the electrolyte of solid oxide fuel cells, Solid State Ionics, 177 , 2053-2057, 2006.01.
407. Shogo Miyoshi, Tetsuro Furuno, Hiroshige Matsumoto, Tatsumi Ishihara, Conductivity and oxygen permeability of a novel oxide Pr2Ni0.8-χCu0.2FeχO4and its application to partial oxidation of CH4, Solid State Ionics, 177 , 2269-2273, 2006.01.
408. Tatsumi Ishihara, Jingwang Yan, Masashi Shinagawa, Hiroshige Matsumoto, Ni-Fe bimetallic anode as an active anode for intermediate temperature SOFC using LaGaO3 based electrolyte film, Electrochimica Acta, 52,pp.1645-pp.1650, 2006.01.
409. Jingwang YAN, Makiko ENOKI, Hiroshige MATSUMOTO, and Tastumi ISHIHARA, An Intermediate Temperature Solid Oxide Fuel Cell using a La(Sr)Ga(Mg)O3 Thin Film Prepared by Pulsed Laser Deposition as Electrolyte, Electrochemistry, 73, 11, 945-950, 73,No.11,pp.945-pp.950, 2005.11.
410. Jingwang Yan, Hiroshige Matsumoto, Makiko Enoki, and Tatsumi Ishihara, High-Power SOFC Using La0.9Sr0.1Ga0.8Mg0.2O3-d/Ce0.8Sm0.2O2-d CompositeFilm, Electrochem. Solid State Lett, 10.1149/1.1943568, 8, 8, A389-A391, 8, p.A389-391, 2005.08.
411. Jingwang Yan, Hiroshige Matsumoto, and Tatsumi Ishihara, Nanosize Effect on the Oxide Ionic Conductivity of Lanthanum Germanite Thia Films, Electrochemical and Solid-State Letters, 10.1149/1.2041333, 8, 11, A607-A610, 8(11)A607-A610, 2005.08.
412. Tatsumi Ishihara, Development of Intermediate-Temperature Solid Oxide Fuel Cells for Hydrocarbon Fuels, Proceedings International Hydrogen Energy Congress and Exhibition IHEC 2005, 2005.07.
413. Atanu Dutta, Tatsumi Ishihara, Amperometric NOx sensor based on oxygen pumping current by using LaGaO3-based solid electrolyte for monitoring exhaust gas, Sensors and Actuators, 10.1016/j.snb.2004.11.076, 108, 1-2, 309-313, B 108 , pp.309-pp.313, 2005.01.
414. Atanu Dutta, Tatsumi Ishihara, Amperometric hydrocarbon sensor using La(Sr)Ga(Fe)O3-solid electrolyte for monitoring in exhaust gas, Sensors and Actuators, 10.1016/j.snb.2005.10.042, 108, 1-2, 368-373, B 108 , pp.368-pp.373, 2005.01.
415. Tatsumi Ishihara, Yoshimasa Ohura, Satoshi Yoshida, Yuiko Hata, Hiroyasu Nishiguchi, Yusaku Takita, Synthesis of hydrogen peroxide by direct oxidation of H2 with O2 on Au/SiO2 catalyst, Applied Catalysis A : General, 10.1016/j.apcata.2005.01.045, 291, 1-2, 215-221, 291 , pp.215-pp.221, 2005.01.
416. Tatsumi Ishihara, Masashi Nakasu, Masaki Yoshio, Hiroyasu Nishiguchi, Yusaku Takita, Carbon nanotube coating silicon doped with Cr as high capacity anode, Journal of power Sources, 10.1016/j.jpowsour.2005.03.110, 146, 1-2, 161-165, 146,pp.161-pp.165, 2005.01.
417. Bustam M. Azmi, Tatsumi Ishihara, Hiroyasu Nishiguchi, Yusaku Takita, LiVOPO4 as a new cathode materials for Li-ion rechargeable battery, Journal of power Sources, 10.1016/j.jpowsour.2005.03.101, 146, 1-2, 525-528, 146,pp.525-pp.528, 2005.01.
418. Tatsumi Ishihara, Satoko Fukui, and Hiroshige matsumoto, Effects of Water Coexisting on the Cathode Activity for the Solid Oxide Fuel Cells Using LaGaO3-Based Perovskite Oxide Electrolyte, Journal of The Electrochemical Society, 10.1149/1.2032407, 152, 10, A2035-A2039, 152(10)A2035-A2039, 2005.01.
419. Jun AKIKURA, Takashi YAMADA, Takafumi KOTANI, Naoya MURAKAMI, Taner AKBAY, Akihiko HASEGAWA, Masaharu YAMADA, and Norikazu KOMADA, Sin NAKAMURA, Norihisa CHITOSE, Katsuya HIRATA, Sigeru SATO, Takashi MIYAZAWA, Makoto SHIBATA, and Kei HOSOI, Futoshi NISHIW, Development of Intermediate Temperature SOFC Module and System, Solid Oxide Fuel Cells IX, Vol.1, pp.102-112, 2005.01.
420. Zhenwei WANG, Akira TORIYAMA, Yohtaro YAMAZAKI, Junichiro MIZUSAKI, Tatsuya KAWADA and Tatsumi ISHIHARA, Temperature Distribution Analysis of Air Preheating in a Honeycomb SOFC, Solid Oxide Fuel Cells IX, Vol.1, pp.876-884, 2005.01.
421. Atanu Dutta, Tatsumi Ishihara, Sensitive Amperometric NO Sensor Using LaGaO3-Based Oxide Ion Conducting Electrolyte, Electrochemical and Solid-State Letters, 10.1149/1.1883872, 8, 5, H46-H48, 8(5) H46-H48, 2005.01.
422. T.Ishihara M.Kamimura, I.Yasuda, H.Nishiguchi, and Y.Takita, Hydrogen Storage of Multi-Walled Carbon Nanotubes Obtained by Decomposition of Hydrocarbon over Ni-Li/SiO2, J. Environment Science & Health, 10.1081/LESA-200027018, 39, 10, 2627-2639, A39, 2627-2639, 2004.11.
423. M.Ando, M.Enoki, H.Nishiguchi, T.Ishihara, Y.Takita, Oxide Ion Conductivity and Chemcal Stability of Lanthanum Fluoraides Doped with Oxygen, La(Sr,Na)F3-2xOx, Chemstry of Materials, 16(21), p4109-4115, 2004.09.
424. W.Liu, Z.Song, T.Ikegawa,H.Nishiguchi, T.Ishihara, Y.Takita, Two step synthesis and characterization of thermally stable hexagonal zirconium phosphate, Material Letters, 58, p.3328-3331, 2004.09.
425. Y.Takita, J.Moriyama, Y.Yoshinaga, H.Nishiguchi, T.Ishihara, S.Yasuda, Y.Ueda, M.Kubo, A.Miyamoto, Adsorption of water vapor on the ALPO4-based catalysts and reaction mechanism for CFCs Decomposition, Applied Catalysis A: General,, 271. p.55-60, 2004.08.
426. T.Ishihara, S.Ishikawa, M. Ando, H.Nishiguchi, and Y.Takita, PO2 Dependence of Valence Number of Co in LaGaO3 and its Influence on Partial Electronic and Oxide Ionic Conductivity, Solid State Ionics, 10.1016/j.ssi.2004.07.045, 173, 1-4, 9-15, Vol. 173, 9-15, 2004.08.
427. Y.Takita, J.Moriyama, H.Nishiguchi, T.Ishihara, F.Hayano, T.Nakajo, Decomposition of CCl2F2 over metal sulfate catalysts, Catalysis Today, 88(15), P103-109(2004), 2004.08.
428. T.Ishihara, N.S.Baik, N.Ono, H.Nishiguchi, Y.Takita, Effect of crystal structure on photolysis of H2O on K-Ta mixed oxide, Journal of Photochemistry and Photobiology A:Chemistry,, 10.1016/j.jphotochem.2004.03.030, 167, 2-3, 149-157, 167, p149-157, 2004.07.
429. Li Ngee Ho, T.Ishihara, S.Ueshima, H.Nishiguchi, Y.Takita, Removal of fluoride from water through ion exchange by mesoporous Ti oxohydroxide, Journal of Colloid and Interface Science, 272, p.399-403, 2004.07.
430. Tatsumi Ishihara, Intermediate temperature solid oxide fuel cells using LaGaO3 based perovskite oxide, Solid State Ionics:The Science And Technology of Ions in Motion, 10.1142/9789812702586_0004, 47-58, p.47-58, 2004.06.
431. M.Nakasu, T.Ishihara, H.Nishiguchi,Y.Takita, Improvement in aodic performance of Si for Li ion rechargeable battery by coating with carbon nanotubes, Solid State Ionics:The Science And Technology of Ions in Motion, p.511-518, 2004.06.
432. M.Koga, T.Ishihara, B.M. Azmi, H.Nishiguchi, Y.Takita, Electrochemical intercalation of PF6- ion in graphitic carbon as a new positive electrode for Li ion rechargeable battery, Solid State Ionics:The Science And Technology of Ions in Motion, p.503-510, 2004.06.
433. M.Sinagawa, T.Ishihara, H.Nishiguchi, Y.Takita, Improvement of anodic performance of Ni by additives on solid oxide fuel cells using LaGaO3 based oxide, Solid State Ionics:The Science And Technology of Ions in Motion, p.171-178, 2004.06.
434. Atanu Dutta, T.Ishihara, H.Nishiguchi, Y.Takita, Amperometric Solid-State Gas Sensor Using LaGaO3 Based Perovskite Oxide Electrolyte for Detecting Hydrocarbon in Exhaust Gas - Ⅱ. Improvement of Inactive Electrode Performance, Journal of The Electrochemical Society, 151(5), p.H122-H127, 2004.05.
435. T.Ishihara, T.Shibayama, S.Ishikawa, K.Hosoi, H.Nishiguchi, Y.Takita, Novel fast oxide ion conductor and application for the electrolyte of solid oxide fuel cell, Journal of the European Ceramic Society, 24, p1329-1355, 2004.04.
436. Fumiaki Mitsugi, Seiji Kanazawa, Toshikazu Ohkubo, Yukiharu Nomoto,, As-Deposited (La1-XSrX)(Ga1-y-zMgyCoz)O3-(x+y+z)/2 Crystallized Thin Films Prepared by Pulsed Laser Deposition for Application to Solid Oxide Fuel Cell Electrolyte, Japanese J. Appl. Phys,, 43, 299-302 (2004)., 2004.01.
437. T.Ishihara, A.Kawahara, H.Nishiguchi, M.Yoshio, Y.Takita, Effects of manganese acetate on the anodic performance of carbon nanotubes for Li ion rechargeable batteries, Journal of Power Soueces, Vol.119-121, p.24-27 (2003), 2003.07.
438. Tatsumi Ishihara, Hiroshi Arikawa, Hiroyasu Nishiguchi, Yusaku Takita, Fast oxide ion conductivity and oxygen tracer diffusion in doped La2GeO5-δ, Solid State Ionics, 10.1016/S0167-2738(02)00481-2, 154-155, 455-460, 2002.12, Oxide ion conductivity in La-deficient La2GeO5-δ was investigated with 18O tracer diffusion measurement. It was found that La1.61GeO4.415 exhibits a large diffusion coefficient, which is in good agreement with that estimated from electrical conductivity. Therefore, it was confirmed that La-deficient La2GeO5 is a pure oxide ionic conductor. The effects of doping alkaline earth cations to the La site of La1.8GeO4.7 were also investigated. Although the crystal structure was slightly changed, alkaline earth cations seem to substitute for the La site in La2GeO5. The electrical conductivity at low temperature is increased by doping alkaline earth cations, in particular, it was found that doping with Ca is the most effective for increasing the electrical conductivity. The electrical conductivity increased with increasing Ca and attained the maximum at a composition of La1.5Ca0.2GeO4.45. The transport number of the oxide ion, estimated by H2-O2 cell, was almost 1.0. Therefore, Ca-doped La2GeO5 oxide is also a pure oxide ionic conductor. Since the electrical conductivity of La1.5Ca0.2GeO4.45 was higher than that of Zr0.84Y0.15O2 at all temperature examined, Ca-doped La2GeO5 based oxide is attractive as a new fast oxide ion conductor..
439. Tatsumi Ishihara, Yuko Tsuruta, Toshitsune Todaka, Hiroyasu Nishiguchi, Yusaku Takita, Fe doped LaGaO3 perovskite oxide as an oxygen separating membrane for CH4 partial oxidation, Solid State Ionics, 10.1016/S0167-2738(02)00413-7, 152-153, 709-714, 2002.12, Fe doped LaGaO3 based perovskite oxide was investigated in this study as an oxygen permeating membrane for CH4 partial oxidation. La0.7Sr0.3Ga0.6Fe0.4O3 exhibits a high oxygen permeation rate from air to He as high as 102 μmol/min cm2 (2.5 cm3-std/min·cm2) at 1273 K and 0.3 mm thickness. Application of LSGF membrane for CH4 partial oxidation was further studied. Since the Po2 difference became large, oxygen permeation rate drastically increased and it attained a value of 322 μmol/min cm2 (8 cm3/min cm2) at 1273 K and 0.5 mm thickness. Catalyst for CH4 partial oxidation has a great influence on oxygen permeation rate through membrane and it became clear that Ni and Ru are highly active for CH4 partial oxidation..
440. Tatsumi Ishihara, Satoko Fukui, Hiroyasu Nishiguchi, Yusaku Takita, Mixed electronic-oxide ionic conductor of BaCoO3 doped with La for cathode of intermediate-temperature-operating solid oxide fuel cell, Solid State Ionics, 10.1016/S0167-2738(02)00394-6, 152-153, 609-613, 2002.12, Mixed electronic-oxide ionic conductivity and the cathodic property of BaCoO3 doped with La was investigated in this study for a solid oxide fuel cell (SOFC) operating at intermediate temperature. The electrical conductivity of BaCoO3 increases systematically with increasing amounts of La doped for Ba site. Cathodic overpotential at 1073 K decreased with increasing La content and attained a minimum at X=0.3-0.4 in Ba1-XLaXCoO3. Since the cathodic overpotential of Ba0.6La0.4CoO3 was small at decreased temperature, Ba0.6La0.4CoO3 is the optimum composition for a cathode of intermediate-temperature fuel cells among BaCoO3-based oxides. Mixed conductivity and surface activity for oxygen dissociation was investigated with 18O-16O exchange reaction. It was found that BaCoO3 doped with La exhibits a large oxide ion conductivity and surface activity. When La0.8Sr0.2Ga0.8Mg0.115Co0.05 O3 (0.4 mm in thickness) was used as electrolyte, the power density of a cell using Ba0.6La0.4CoO3 for the cathode at 873 K attained a value of 120 mW/cm2, which is slightly larger than that using a conventional Sm0.5Sr0.5CoO3 oxide for the cathode..
441. Seiji Kanazawa, Takeshi Ito, Kenji Yamada, Toshikazu Ohkubo, Yukiharu Nomoto, Tatsumi Ishihara, Yusaku Takita, Preparation of doped lanthanum gallate electrolyte for SOFC by pulsed laser deposition, Materials for Energy Storage, Generation and Transport Materials Research Society Symposium - Proceedings, 730, 179-184, 2002.12, In this study, doped lanthanum gallate (LSGM with the composition La0.9Sr0.1Ga0.8Mg0.2O3-, LSGMC with the composition La0.8Sr0.2Ga0.8Mg0.15Co0.05 O3-) films for an electrolyte of the solid oxide fuel cell (SOFC) were prepared by pulsed laser deposition (PLD) technique. In the vacuum chamber, LSGM or LSGMC targets were set on the rotating target holder. A KrF excimer laser was introduced into the chamber at an incident angle of about 45 degree. The doped LaGaO3 film was deposited onto NiO substrates without heating in argon ambient gas. The NiO substrate can be used directly as an electrode in the fabrication of the SOFC. The deposited LSGM films were characterized by X-ray diffraction (XRD), secondary ion mass spectroscopy (SIMS) and scanning electron microscopy (SEM). As-deposited films were amorphous. After post annealing at 1273K for 6-10 hours, crystalline LaGaO3 was obtained. Films with thickness greater than several 10 m showed an uniform and dense morphology. No gas leakage was found using thick films, which is an important characteristic for an electrolyte in fuel cells. The composition of the deposited films was slightly different to that of the target..
442. Bustam M. Azmi, Tatsumi Ishihara, Hiroyasu Nishiguchi, Yusaku Takita, Cathodic performance of VOPO4 with various crystal phases for Li ion rechargeable battery, Electrochimica Acta, 10.1016/S0013-4686(02)00597-2, 48, 2, 165-170, 2002.11, Cathodic performance of six different VOPO4 phases for Li ion rechargeable battery was investigated. It was found that VOPO4 exhibits a high flat discharge potential of 3.7 V for Li ion electrochemical intercalation and de-intercalation excepting for β- and -types. On the other hand, slightly higher flat discharge potential of 3.9 and 3.8 V was observed for β- and -types. Capacity for Li intercalation is strongly related with the crystal structure of VOPO4. In particular, δ-phase exhibits the largest reversible capacity of ca. 130 mAh/g among the examined VOPO4. High capacity for Li intercalation in δ-phase VOPO4 hardly decreased over 30 times of charge and discharge cycles. Although the reversible capacity decreased with increasing the current density for charge and discharge, large capacity of 80 mAh/g was still sustained at 0.4 mA/cm2 for δ-type VOPO4..
443. Bustam M. Azumi, Tatsumi Ishihara, Hiroyasu Nishiguchi, Yusaku Takita, Electrochemical intercalation of Li into heteropoly 12 molybdophosphoric acid ion-exchanged with Cs, Electrochemistry, 70, 11, 869-874, 2002.11, Electrochemical Li intercalation properties in 12-molybdophosphoric and 12-tangstophosphoric acids were investigated. It was found that both 12-molybdophosphoric and 12-tangstophosphoric acids exhibit fairly large capacity for the Li intercalation. Flat potential of 12-tangstophosphoric acids was 0.5 V, which could be used for the anode of Li ion battery. 12-molybdophosphoric acid exhibits the flat potential of 1.5 V, although cycle stability is not high. XRD measurement shows the formation of Li2MoO4 after the intercalation of Li. Therefore electrochemical Li intercalation occurs by redox between Mo6+ and Mo4+ and so the theoretical Li intercalation capacity in 12-molybdophosphoric acid is 373 mAh/g. Ion-exchanging H+ in 12-molybdophosphoric acid to Cs+ is effective to improve the cycle stability and capacity of ca. 200 mAh/g is sustained after 10 cycles. De-intercalation potential of 4.0 V is newly appeared by substitution of Mo in 12-molybdophosphoric acid with V although the capacity is still not large. Therefore, substitution of V is effective for increasing the Li intercalation potential..
444. Yoshiaki Obana, Kazuya Eto, Masami Ito, Qing Xia, Hiroyasu Nishiguchi, Tatsumi Ishihara, Yusaku Takita, Selective oxidation of isobutane to methacrolein by the combined oxide catalysts, Ni2P2O7 for oxidative dehydrogenation of alkanes and Bi-Mo-oxide, Sekiyu Gakkaishi (Journal of the Japan Petroleum Institute), 45, 6, 375-381, 2002.11, Direct formation of methacrolein from isobutene was studied using a combination of the catalyst effective for oxidative dehydrogenation of isobutene, Ni2P2O7, and the catalyst effective for selective oxidation of olefins, Bi-Mo12-Fe-Co6-Ni2Cs0.1 4-oxide. Methacrolein was formed with the selectivity as high as 65% in a reactor with two catalyst beds in series. A catalyst consisting of a mixture of the powders of both catalysts was effective for isobutene formation, although the conversion was reduced, whereas a mixture of granules was less effective. Addition of water vapor to the reaction system reduced the formation of oxygenates and promoted the formation of isobutene..
445. Shizhong Wang, Tatsumi Ishihara, Yusaku Takita, Dimethyl ether fueled intermediate temperature SOFC using LaGaO3-based perovskite electrolytes, Electrochemical and Solid-State Letters, 10.1149/1.1489135, 5, 8, 2002.08, Intermediate temperature solid oxide fuel cells (SOFCs) fueled with dimethyl ether (DME) were investigated. The performance of a single cell, Ni/La0.9Sr0.1Ga0.8Mg0.2O3 /Sm0.5Sr0.5O3, fueled with DME was comparable to that of the cell fueled with hydrogen at 1073 K. However, the power density of the DME cell decreased dramatically with decreasing temperature and showed lower maximum power density than H2 cell at 973 K due to high anodic overpotential. The oxidation of DME on Ni was rather complex, and there were at least two arcs in the impedance spectra under polarization, while there was only one arc when the anode was exposed to H2. The activity of the anode was improved greatly by using Ni-Sm3+ doped ceria (Ni-SDC) composite anode or Ni-SDC/SDC bilayer anode. DME decomposition into CH4, CO, and H2 takes place at the first step, and the overall reaction is close to the partial oxidation of DME into CO and H2 with increasing current density..
446. Tatsumi Ishihara, Akihiro Kawahara, Akira Fukunaga, Hiroyasu Nishiguchi, Hidetoshi Shinkai, Masahiro Miyaki, Yusaku Takita, CH4 decomposition with a Pd-Ag hydrogen-permeating membrane reactor for hydrogen production at decreased temperature, Industrial and Engineering Chemistry Research, 41, 14, 3365-3369, 2002.07, The decomposition of CH4 into C and H2 over Ni/SiO2 was investigated with a Pd-Ag hydrogen-permeating membrane reactor. The CH4 decomposition reaction hardly proceeded at temperatures lower than 773 K in a conventional fixed-bed reactor because of a chemical equilibrium limit. However, the conversion of CH4 was dramatically increased by removing the formed hydrogen by the Pd-Ag membrane. Because higher CH4 decomposition conversions were achieved at higher hydrogen removal rates in the Pd-Ag membrane, the removal of the formed hydrogen seems to be the key step for CH4 decomposition reaction at decreased temperature. Because a higher hydrogen permeation rate was achieved on the Pd(77)-Ag(23) membrane than on the Pd(90)-Ag(10) membrane, the CH4 conversion was always higher in membrane reactors using Pd(77)-Ag(23) than in reactors using Pd(90)-Ag(10) for the hydrogen separation membrane. The CH4 conversion increased with increasing contact time of the reactant and/or with increasing sweep Ar flow rate, because the hydrogen removal rate was improved. Consequently, this study revealed that CH4 decomposition into CO and H2 can occur with sufficiently high conversion (gt;88%) at 773 K and this process can provide hydrogen at decreased temperature..
447. Tatsumi Ishihara, Satoko Fukui, Hiroyasu Nishiguchi, Yusaku Takita, La-doped BaCoO3 as a cathode for intermediate temperature solid oxide fuel cells using a LaGaO3 base electrolyte, Journal of the Electrochemical Society, 10.1149/1.1480015, 149, 7, 2002.07, Cathodic behavior of BaCoO3 doped with La was investigated in this study for an intermediate temperature solid oxide fuel cell (ITFC). Electrical conductivity of BaCoO3 increased monotonically with an increasing amount of La doped for the Ba site at 1073 K po(2) = 10-5 atm. Cathodic overpotential at 1073 K decreased with increasing La content and attained a minimum at X = 0.3-0.5 in Ba1-xLaxCoO3. Since the cathodic overpotential of Ba0.6La0.4CoO3 kept a small value at decreased temperature, Ba0.6La0.4CoO3 is the optimum composition for the cathode of an ITFC among BaCoO3-based oxides. When La0.8Sr0.2Ga0.8Mg0.15Co0.05 O3 was used for the electrolyte, the power density of the cell using Ba0.6La0.4CoO3 for the cathode at 1073 K attained a value of 550 mW/cm2, which is slightly higher than that using Sm0.5Sr0.5CoO3 for the cathode. In addition, a low cathodic overpotential of Ba0.6La0.4CoO3 was also maintained in air. 18O-16O exchange reaction was performed to estimate the surface activity for oxygen dissociation. It was found that BaCoO3 exhibits high activity for the oxygen exchange reaction. Therefore, superior cathode property was assigned to the high surface activity of BaCoO3..
448. Yusaku Takita, Toshiko Tanabe, Masami Ito, Masaru Ogura, Toshio Muraya, Sachio Yasuda, Hiroyasu Nishiguchi, Tatsumi Ishihara, Decomposition of CH2FCF3 (134a) over metal phosphate catalysts, Industrial and Engineering Chemistry Research, 41, 11, 2585-2590, 2002.05, The decomposition of CH2FCF3 over some phosphate catalysts was studied. CH2FCF3 began to react at 250, 300, and 450 °C over Zr3(PO4)4, AlPO4, and BPO4, respectively, and the conversion reached 100% at 475, 500, and 700 °C, respectively. The primary reaction over Zr3(PO4)4 was estimated to be CH2FCF3 + H2O + 1/2O2 → 2CO + 4HF, whereas the reactions over AlPO4 and BPO4 were CH2FCF3 + H2O + O2 → CO + CO2 + 4HF and CO + 1/2O2 → CO2. Complete decomposition requires both hydrolysis and oxidation. The oxidation activities of these phosphate catalysts are not high enough to accomplish complete decomposition. However, AlPO4-based catalysts can be combined with each Co3O4, Mn2O3, CuO, and Cr2O3 at a phosphate content of 1/10 by volume to make them sustainable at 550-550 °C. The addition of Ce to AlPO4 brought about a promotion effect in CH2FCF3 decomposition similar to that for CCl2F2 decomposition. This might suggest a similarity in the reaction mechanism. The primary reaction in the absence of oxygen was estimated to be CH2FCF3 + H2O → CO + C + 4HF..
449. Shizhong Wang, Tatsumi Ishihara, Yusaku Takita, Partial oxidation of dimethyl ether over various supported metal catalysts, Applied Catalysis A: General, 10.1016/S0926-860X(01)00985-1, 228, 1-2, 167-176, 2002.05, Partial oxidation of dimethyl ether (DME) on various metal catalysts was investigated. DME was highly active for oxidation and could be partially oxidized into CO and H2 at a temperature lower than 600 K on most of the examined supported metal catalysts. The products of partial oxidation of DME depended strongly not only on the metal catalyst but also on the oxide support. Formation of CO, H2, CH4, HCHO, CO2, and H2O were observed on Al2O3-supported catalysts. However, no HCHO was formed on the catalysts supported on SiO2, MgO, Y0.16Zr0.84O2 (YSZ), Ce0.85Sm0.15O3, and LaGaO3 based oxide, i.e. La0.8Sr0.2Ga0.8Mg0.15Co0.05 O3 (LSGMC). The activity to partial oxidation of DME on catalysts supported on Al2O3 increased in the order of Ni > Rh > Co ≫ Ru > Fe > Pt ≫ Ag. In particular, Ni supported on LaGaO3 based oxide was active and selective for partial oxidation of DME into synthesis gas. Effects of reaction conditions were further studied on Ni/LSGMC. Selectivity to CO and H2 increased with decreasing contact time. Therefore, primary products of this reaction are CO and H2 and the byproduct CH4 seems to be a secondary product. A small amount of coke was formed on Ni/LSGMC at low reaction temperatures; however, the amount was tiny at high temperatures..
450. Y. Takita, S. Yoshida, K. Usami, T. Sato, Y. Obana, M. Ito, M. Ogura, H. Nishiguchi, T. Ishihara, Promotion effects of an extremely low concentration of noble metals supported onto Bi2Mo3O12 on the partial oxidation of iso-butane, Applied Catalysis A: General, 10.1016/S0926-860X(01)00877-8, 225, 1-2, 215-221, 2002.02, Supporting extremely small concentrations of noble metals on SiO2 and Bi2Mo3O12 affected the catalytic activity and product distribution in iso-butane partial oxidation. Supporting Pt, Pd, and Rh onto SiO2 by 1 atom/μm2 enhanced the catalytic activity. Selectivity values of partial oxidation products, iso-butene, CH3C(CH3)CHO, CH3CHO and CH3COCH3, were increased and COx selectivity was decreased. Rh/SiO2 gave an EPR signal due to isolated Rh2+ ions with g⊥ = 2.07 and g∥ = 1.95, suggesting that two valent Rh ions are well dispersed on the surface and play a role in the oxidation of iso-butane. Supporting Pd, Ir, Rh, and Au onto Bi2Mo3O12 at a concentration of (1/9) × 10-4atom/nm2 increased the conversion, but supporting Pt and Ru decreased it. Selectivity values of CH2=C(CH3)CHO and COx were the same for every catalyst. Catalytic activity was increased by supporting them by (1/49) × 10-4 atom/nm2; especially, supporting Rh increased the activity without changing the selectivity of CH2=C(CH3)CHO. Supported noble metal will interact with active oxygen ions bridging Mo and Bi on the Bi2Mo3O12 surface. Since a certain concentration of supported noble metals, (1/49) × 10-4nm2, begins to affect the catalytic activity and selectivity, this concentration may reflect the concentration of active sites in iso-butane oxidation at 350-400°C over Bi2Mo3O12..
451. M. Sharon, W. K. Hsu, H. W. Kroto, D. R.M. Walton, A. Kawahara, T. Ishihara, Y. Takita, Camphor-based carbon nanotubes as an anode in lithium secondary batteries, Journal of Power Sources, 10.1016/S0378-7753(01)00872-2, 104, 1, 148-153, 2002.01, Camphor vapour is pyrolysed in the presence of Fe, Ni and Co powder under a dinitrogen atmosphere at different temperatures (750-1050°C). While Fe and Ni catalyse the formation of carbon nanotubes (CNs), Co facilitates carbon nanobead growth. The CNs, obtained using a Fe catalyst at 950°C, are utilised as the anode in Li secondary batteries. The capacity of the batteries constructed in this way is as good as those prepared by graphitic carbon formed in the arc process..
452. Junichi Moriyama, Hiroyasu Nishiguchi, Tatsumi Ishihara, Yusaku Takita, Metal sulfate catalyst for CCl2F2 decomposition in the presence of H2O, Industrial and Engineering Chemistry Research, 41, 1, 32-36, 2002.01, Activities for the hydrolysis of CCl2F2 (CFC-12) on various metal sulfates were investigated in this study. It was found that Zr(SO4)2 exhibits a high activity for CFC-12 decomposition and a high selectivity to CO2. On the other hand, the metal sulfates Al2(SO4)3, La2(SO4)3, Ce2(SO4)3, and Cr2(SO4)3 were also active for the hydrolysis of CFC-12. However, the activities for CFC-12 decomposition of MnSO4, CoSO4, and MgSO4 were low, and decomposition of CFC-12 hardly occurred on the metal sulfates CaSO4, SrSO4, and BaSO4. Among the investigated metal sulfates, Zr(SO4)2 was the most active, and the complete decomposition of CFC-12 was achieved at 598 K. The CFC-12 decomposition rate monotonically increased with increasing CFC-12 partial pressure. On the other hand, CFC-12 conversion became highest at an oxygen content of 18.9 mol % and a H2O content of 5 mol %. Therefore, the main reaction on Zr(SO4)2 for CFC-12 decomposition into CO2 and HCl and HF is the hydrolysis reaction. The high activity to CFC-12 decomposition on Zr(SO4)2 was stably sustained over the 40-h period examined. Therefore, the metal sulfate Zr(SO4)2 is highly active for the hydrolysis of CFC-12 and has sufficient stability against fluorination and/or chlorination..
453. T. Ishihara, Y. Tsuruta, H. Nishiguchi, Y. Takita, Partial oxidation of CH4 by oxygen-permeating membrane reactor using LaGaO3 doped with Fe and Sr, Sekiyu Gakkaishi (Journal of the Japan Petroleum Institute), 10.1627/jpi.45.32, 45, 1, 32-38, 2002.01.
454. Tatsumi Ishihara, Yasuhiro Shuto, Soichiro Ueshima, Ho Li Ngee, Hiroyasu Nishiguchi, Yusaku Takita, Titanium hydroxide as a new inorganic fluoride ion exchanger, Journal of the Ceramic Society of Japan, 10.2109/jcersj.110.801, 110, 1285, 801-803, 2002.01, Although TiO2 exhibits a small fluoride ion exchange capacity, it was found that titanium hydroxide, Ti(OH)4, can exchange fluoride ion with large saturation capacity of 1.60 m ̇ mol/g. Although the H2PO4 - interferes with the F- exchange, the amount of F- exchange of Ti(OH)4 was hardly changed by the coexistence of Cl-, NO3 -, and SO4 2-. The capacity for F- exchange was almost unchanged over 4 times repetition of ion-exchange and desorption and furthermore, the elution of Ti was negligibly small. Consequently, Ti(OH)4 is expected to be a new inorganic F- exchanger for the removal of fluoride ion from wastewater..
455. Jun Akikusa, Kazunori Adachi, Koji Hoshino, Tatsumi Ishihara, Yusaku Takita, Development of a Low Temperature Operation Solid Oxide Fuel Cell, Journal of the Electrochemical Society, 10.1149/1.1409972, 148, 11, 2001.11, Lowering operation temperature of the solid oxide fuel cell (SOFC) would promote the commercialization of a power-generation module in terms of the manufacturing cost, lifetime, reliability, etc. Mitsubishi Materials Corporation and Oita University have been jointly developing a planar-type SOFC which could operate at a temperature of about 700°C. As an electrolyte, lanthanum gallate (LaGaO3) with substitution of Sr for the La site and Mg and Co for the Ga site was used at this temperature. So far we have established a technique for large-scale cell production, and currently we are examining the performance of a commercial-size cell as large as 154 mm in diam. The obtained cell attained an output power of 31 W with an effective electrode area of 177 cm2 at 650°C. Furthermore, a stuck of two cells has been tested and the use of stainless steel for the separator was found to be possible during the examined time period at this temperature. The internal CH4 reforming on the cell has been examined, and the cell output performance using methane [steam/carbon ratio (S/C) = 2 ] was about 93% of the power density of the cell using hydrogen..
456. Takashi Takeuchi, Shingo Watanabe, Yoshiyasu Hatano, Miki Kuwano, Yukari Eguchi, Kazuaki Yoshida, Tatsumi Ishihara, Yusaku Takita, Current-Voltage Characteristics of Various Metal Electrodes in Limiting-Current-Type Zirconia Cells Application to Hydrocarbon Sensors, Journal of the Electrochemical Society, 10.1149/1.1388888, 148, 9, 2001.09, The influence of electrode materials on the current vs. voltage characteristics of limiting-current-type zirconia cells has been investigated systematically. The cells have one or two pairs of electrodes consisting of Pt, Pd, Au, or Ag, and a cover with a pinhole, which serves to limit gas diffusion and, therefore, the electrical current of the cells. The limiting current was found to depend definitely on the catalytic activity of the electrodes for the oxidation reaction of hydrocarbon gases in oxygen and hydrocarbon-containing gases. The results were applied to improve the sensitivity of limiting-current hydrocarbon sensors. The highest sensitivity was attained for the following combination of electrodes: Pt and Ag inner electrodes and a Au outer electrode in two-inner-electrode sensors. A preliminary examination has also been made on a three-inner-electrode sensor..
457. Tatsumi Ishihara, Akihiro Kawahara, Hiroyasu Nishiguchi, Masaki Yoshio, Yusaku Takita, Effects of synthesis condition of graphitic nanocabon tube on anodic property of Li-ion rechargeable battery, 10th International Meeting on Lithium Batteries Journal of Power Sources, 10.1016/S0378-7753(01)00614-0, 97-98, 129-132, 2001.07, Effects preparation condition of multiwall carbon nanotube on Li intercalation were investigated in this study. Both Li intercalation and reversible capacities increased with increasing contact time of CH4 on Ni catalyst when the multiwall carbon nanotube was prepared. Raman spectroscopy suggested that the content of graphitic carbon tube increased with increasing the contact time of CH4 upon synthesis. Therefore, in case of tubular carbon, graphitic carbon also exhibited a larger capacity for Li intercalation comparing with that of amorphous one. Intercalation and reversible capacity for Li insertion at first cycle were attained to a value of 430 and 320 mAh/g, respectively, on the carbon nanotube obtained at the contact time higher than 100 g-cath/mol..
458. Yuko Tsuruta, Toshitsune Todaka, Hiroyasu Nisiguchi, Tatsumi Ishihara, Yusaku Takita, Mixed electronic-oxide ionic conductor of Fe-doped La(Sr)GaO3 perovskite oxide for oxygen permeating membrane, Electrochemical and Solid-State Letters, 10.1149/1.1347224, 4, 3, 2001.03, Oxygen permeating property of Fe doped LaGaO3 based perovskite oxide was investigated in this study. Fe doped La1-xSrxGaO3 exhibits high total conductivity (∼103 S/cm) and high oxygen permeation rate. In particular, the highest total conductivity and oxygen permeating rate were attained at La0.7Sr0.3Ga0.6Fe0.4O3. At this composition, oxygen permeation rate from air to He was as high as 2.5 cm-2/min · cm-2 at 1273 K and 0.3 mm membrane thickness..
459. T. Ishihara, T. Shibayama, H. Nishiguchi, Y. Takita, Oxide ion conductivity in La0.8Sr0.2Ga0.8Mg0.2-xNix O3 perovskite oxide and application for the electrolyte of solid oxide fuel cells, Journal of Materials Science, 10.1023/A:1004821607054, 36, 5, 1125-1131, 2001.03, Although hole conduction was present, it was found that doping with Ni was effective in improving the oxide ion conductivity in La0.8Sr0.2Ga0.8Mg0.2O3 based perovskite oxides. Considering the ionic transport number and the electrical conductivity, the optimized composition for Ni doped samples was La0.8Sr0.2Ga0.8Mg0.13 Ni0.07O3 (LSGMN). In t composition, electrical conductivity was found to be virtually independent of the oxygen partial pressure from 1 to 10-21 atm. Consequently, the oxide ion conductivity was still dominant in this optimized composition. In agreement with the improved oxide ionic conductivity, the power density of the solid oxide fuel cell using LaGaO3 as an electrolyte increased by doping with a small amount of Ni on the Ga site. In particular, the power density of 224 mW/cm2 at 873 K, which is the maximum power density in the cells using LaGaO3 based oxide as the electrolyte, was attained using LSGMN in spite of the use of electrolyte plates with a thickness of 0.5 mm. Therefore, LSGMN is highly attractive for the electrolyte material of low temperature operating SOFCs..
460. M. Kagawa, H. Kawamura, S. Kimura, H. Nishiguchi, Tatsumi Ishihara, Y. Takita, Reduction of NO with CH4 over platinum supported on cobalt phosphate catalyst, JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, 34, 3, 69-75, 2001.03, A study on the selective reduction of NO with CH4 on platinum supported on cobalt phosphate showed that Pt/Co3(PO4)2 exhibited the highest activity to NO reduction with CH4. NO conversion increased with increasing amount of Pt loading and attained a maximum activity at 1 wt % Pt. NO conversion was always higher than that of NO2 on Pt/Co3(PO4)2 under the same condition. The reduction of NO was proceeded through the direct decomposition of NO as a primary reaction. NO conversion increased with decreasing oxygen partial pressure and the high conversion of NO into N2 was exhibited when no oxygen coexisted. TPD measurement suggested that loading Pt accelerated the dissociative adsorption of NO and weakened the O2. Thus, NO decomposition on Pt/Co3(PO4)2 seemed to be initiated by the dissociative adsorption of NO. Coexisting CH4 removed the formed oxygen that strongly adsorbed on the catalyst and recovered the active site. Pt supporting on Co3(PO4)2 was highly active for the reduction of NO with CH4..
461. Tatsumi Ishihara, H. Arikawa, Taner Akbay, H. Nishiguchi, Y. Takita, Nonstoichiometric La2-xGeO5-δ monoclinic oxide as a new fast oxide ion conductor, Journal of the American Chemical Society, 10.1021/ja0014537, 123, 2, 203-209, 2001.01, Oxide ion conductivity in La2GeO5-based oxide was investigated and it was found that La-deficient La2GeO5 exhibits oxide ion conductivity over a wide range of oxygen partial pressure. The crystal structure of La2GeO5 was estimated to be monoclinic with P21/c space group. Conductivity increased with increasing the amount of La deficiency and the maximum value was attained at x = 0.39 in La2-xGeO5-δ. The oxide ion transport number in La2GeO5-based oxide was estimated to be unity by the electromotive force measurement in H2 - O2 and N2 - O2 gas concentration cells. At a temperature higher than 1000 K, the oxide ion conductivity of La1.61GeO5-δ was almost the same as that of La0.9Sr0.1Ga0.8Mg0.2 O3-δ or Ce0.85Gd0.15O2-δ, which are well-known fast oxide ion conductors. On the other hand, a change in the activation energy for oxide ion conductivity was observed at 973 K, and at intermediate temperature, the oxide ion conductivity of La1.61GeO5-δ became much smaller than that of these well-known fast oxide ion conductors. The change in the activation energy of the oxide ion conductivity seems to be caused by a change in the local oxygen vacancy structure. However, doping a small amount of Sr for La in La2GeO5 was effective to stabilize the high-temperature crystal structure to low temperature. Consequently, doping a small amount of Sr increases the oxide ion conductivity of La2-GeO5-based oxide at low temperature..
462. Tatsumi Ishihara, Yusaku Takita, Partial oxidation of methane into syngas with oxygen permeating ceramic membrane reactors, Catalysis Surveys from Japan, 10.1023/A:1011407421210, 4, 2, 125-133, 2001.01, Partial oxidation of methane (CR4 +1/2O2 = CO + 2H2) is considered as an alternative reforming reaction to steam reforming for production of syngas. This reaction is a slightly exothermic reaction and produces syngas of H2/CO = 2, which is suitable for the synthesis of hydrocarbon or methanol. In this paper, the catalytic partial oxidation of CH4 with a membrane reactor using oxygen permeating ceramic, in particular, LaGaO3-based oxide, is reported. Supported Ni or Rh catalysts are active and selective for this reaction. On the other hand, a mixed ionic and electronic conducting (MIEC) ceramic membrane is useful for obtaining pure oxygen from air when the gradient in oxygen partial pressure is obtained. As for a MIEC membrane, mixed electronic-oxide ionic conductors of Fe- or Co-based perovskite oxides are widely investigated. However, the improvement in stability in a reducing atmosphere is critically required for the MIEC membrane for the application to the membrane reactor for CH4 partial oxidation. Perovskite oxides of LaGaO3 doped with Sr for a La site and a Fe, Co, or Ni for a Ga site, respectively, are promising as the oxygen-separating membrane for CH4 partial oxidation because of high stability in a reducing atmosphere as well as high permeability of oxygen. The partial oxidation of CH4 with solid oxide fuel cells (SOFCs) is also described. Simultaneous generation of electrical power and syngas is demonstrated by the fabricated fuel cell type reactor using a LaGaO3-based oxide electrolyte..
463. Masaru Kagawa, Hitoshi Kawamyra, Shuji Kimura, Hiroyasu Nishiguchi, Tatsumi Ishihara, Yusaku Takita, Reduction of NO with CH4 over platinum supported on cobalt phosphate catalyst, kagaku kogaku ronbunshu, 10.1252/kakoronbunshu.27.69, 27, 1, 74-75, 2001.01, Selective reduction of NO with CH4 on platinum supported on cobalt phosphate was investigated. It was found that Pt/Co3(PO4)2 exhibits the high activity to NO reduction with CH4. NO conversion increased with increasing amount of Pt loading and it attained to a maximum activity at 1 wt% Pt. Conversion of NO was always higher than that of NO2 on Pt/Co3(PO4)2 under the same condition. This result suggested that the reduction of NO was proceeded not through the formation of NO2 or NO3- as intermediate species but through the direct decomposition of NO as a primary reaction. NO conversion increased with decreasing oxygen partial pressure and the high conversion of NO into N2 was exhibited when no oxygen was coexisted. Temperature programmed desorption (TPD) measurement suggested that loading Pt accelerates the dissociative adsorption of NO and weakened the adsorption of O2. Therefore, it seems that NO decomposition on Pt/Co3(PO4)2 was initiated by the dissociative adsorption of NO. Coexisting CH4 removed the formed oxygen which strongly adsorbed on the catalyst and recovered the active site. This study reveals that Pt supporting on Co3(PO4)2 is highly active for the reduction of NO with CH4..
464. Tatsumi Ishihara, Takashi Yamada, Hiroshi Arikawa, Hiroyasu Nishiguchi, Yusaku Takita, Mixed electronic-oxide ionic conductivity and oxygen permeating property of Fe-, Co- or Ni-doped LaGaO3 perovskite oxide, Solid State Ionics, 10.1016/S0167-2738(00)00424-0, 135, 1-4, 631-636, 2000.11, Mixed electronic-oxide ionic conductivity in LaGaO3-based oxide doped with Fe, Co or Ni was investigated in this study. The electric conductivity was greatly increased by doping Fe, Co, or Ni for the Ga site of La0.8Sr0.2GaO3. Compared to the conventional mixed electronic-ionic conductors such as LaCoO3, these LaGaO3-based oxides exhibited a lower electronic conductivity but a higher oxide ion conductivity. In particular, Fe-doped LaGaO3 exhibited a high oxygen permeation rate and a stability against reduction. Consequently, higher CH4 conversion in the partial oxidation of CH4 was attained by using La0.8Sr0.2Ga0.6Fe0.4O3 in the place of the conventional candidate material of La0.6Sr0.4Fe0.8Co0.2O3 for the oxygen permeation membrane. As a result, this study revealed that LaGaO3-based oxide doped with Fe, Co or Ni for Ga site is a new family of mixed electronic-oxide ionic conductors..
465. Hiroshi Arikawa, Hiroyasu Nishiguchi, Tatsumi Ishihara, Yusaku Takita, Oxide ion conductivity in Sr-doped La10Ge6O27 apatite oxide, Solid State Ionics, 10.1016/S0167-2738(00)00386-6, 136-137, 31-37, 2000.11, Oxide ion conductivity in La10Si6O27 and La10Ge6O27-based apatite oxides was investigated in this study. In spite of the low symmetry of the crystal lattice, both oxides exhibited high oxide ion conductivity over a wide range of oxygen partial pressures. Oxide ion conductivity of La10Si6O27 was increased by doping Sr for La sites. On the other hand, it was found that La10Ge6O27 also exhibited high oxide ion conductivity which is comparable with that of La0.9Sr0.1Ga0.8Mg0.2O3 perovskite oxide. Arrhenius plots of the oxide ion conductivity in La10Ge6O27 show a knee around 1000 K. However, the knee in the Arrhenius plot of conductivity disappeared by doping Sr for La sites. Thus, the conductivity at low temperature was greatly enhanced by doping Sr for La sites in La10Ge6O26. This may be due to stabilization of the high temperature crystal phase. The electrical conductivities of Sr-doped La10Si6O27 and La10Ge6O27 were almost independent of the oxygen partial pressure from PO(2) = 1 to 10-21 atm. This suggests that these materials are ionic over a wide PO(2) range. This study revealed that apatite oxide of La10M6O27 (M = Si, Ge) is a new class of the fast oxide ion conductors..
466. Tatsumi Ishihara, Kuninobu Shimose, Takanari Kudo, Hiroyasu Nishiguchi, Taner Akbay, Yusaku Takita, Preparation of yttria-stabilized zirconia thin films on strontium-doped LaMnO 3 cathode substrates via electrophoretic deposition for solid oxide fuel cells, Journal of the American Ceramic Society, 83, 8, 1921-1927, 2000.08, A yttria-stabilized zirconia (YSZ) thin film on an La 0.8Sr 0.2MnO 3 porous cathode substrate was prepared, using electrophoretic deposition (EPD) to fabricate a solid oxide fuel cell (SOFC). The electrical conductivity of an La 0.8Sr 0.2MnO 3 substrate is satisfactorily high at room temperature; therefore, YSZ powder could be deposited electrophoretically onto an La 0.8Sr 0.2MnO 3 substrate without any extra surface treatment, such as a metal coating. Successive repetition of EPD and sintering was required to obtain a film without gas leakage, because of the thermal expansion coefficient mismatch between the YSZ and the La 0.8Sr 0.2MnO 3 substrate. On the other hand, the electromotive force of the oxygen concentration in the cell that used YSZ film prepared via EPD increased and attained the theoretical value when the number of deposition and calcination cycles was increased. Six or more successive repetitions were required to obtain a YSZ film without gas leakage. A planar-type SOFC was fabricated, using nickel as the anode and YSZ film ( approximately 10 μm thick) that had been deposited onto the La 0.8Sr 0.2MnO 3 substrate as the electrolyte and cathode. The cell exhibited an open circuit voltage of 1.0 V and a maximum power density of 1.5 W/cm 2. Thus, the EPD method could be used as a colloidal process to prepare YSZ thin-film electrolytes for SOFCs..
467. Kiyoshi Kuroda, Ikiko Hashimoto, Kazunori Adachi, Jun Akikusa, Yoshitaka Tamou, Norikazu Komada, Tatsumi Ishihara, Yusaku Takita, Characterization of solid oxide fuel cell using doped lanthanum gallate, Solid State Ionics, 132, 3, 199-208, 2000.07, The power-generation characteristics and the electrode overpotential of the solid oxide fuel cell (SOFC) using doped lanthanum gallate perovskite-type oxide as and electrolyte were measured at temperatures below that of the typical SOFC using yttria-stabilized zirconia (YSZ) as an electrolyte. The oxide ion conductivity of the electrolyte, La0.8Sr0.2Ga0.8Mg0.15Co0.05O3-δ (LSGMC), was much higher than that of YSZ. A single cell using LSGMC of 205 μm in thickness showed a power density of 380 mW/cm2 at a current density of 0.5 A/cm2 and a temperature of 650 °C by using air and dry hydrogen as oxidant and fuel, respectively. The overpotential of anode was larger than that of the cathode and dominated the overall overpotential. The IR-drop measured by current-interrupting method was in good agreement with the value estimated from the electrical conductivity of the electrolyte. The experimental results indicate that LSGMC is a promising material as an electrolyte for a low-temperature SOFC. The characteristics of electrodes are further discussed in terms of the composition and particle size of the starting powders..
468. Y. Eguchi, S. Watanabe, N. Kubota, T. Takeuchi, T. Ishihara, Y. Takita, Limiting current type sensor for hydrocarbons, IMCS-7: 7th International Meeting on Chemical Sensors Sensors and Actuators, B: Chemical, 10.1016/S0925-4005(99)00465-7, 66, 1, 9-11, 2000.07, A hydrocarbon (HC) sensor, composed of yttria-stabilized zirconia (YSZ) as a solid electrolyte and catalytically active and passive material for HC as electrodes, is proposed. The active and passive electrodes were attached to the same side of a YSZ disk as cathodes. A Pt electrode was applied to the other side of YSZ as anode. The diffusion of gas to the cathodes was limited by a pinhole of a cover attached to YSZ and the sensor showed a limiting current behavior by applying voltage. The difference between the limiting current, ΔI, of two cathodes increased linearly with the concentration of HC such as methane and isobutane, which suggests that HC concentration can be obtained by measuring ΔI..
469. Tatsumi Ishihara, Takaaki Shibayama, Hiroyasu Nishiguchi, Yusaku Takita, Nickel-Gd-doped CeO
2
cermet anode for intermediate temperature operating solid oxide fuel cells using LaGaO
3
-based perovskite electrolyte, Solid State Ionics, 132, 3, 209-216, 2000.07, Ni-CeO
2
doped with 20 mol.% Gd
3+
(GDC) cermet was investigated as the anode of an intermediate temperature operating solid oxide fuel cell using LaGaO
3
-based oxide electrolyte. It was found that the anodic overpotential decreased by mixing Ni with mixed electronic-ionic conductor, in-particular, mixing with doped CeO
2
is the most effective for decreasing the overpotential of the anode. Anodic overpotential became a minimum at 10 vol.% GDC to NiO. Using Ni-GDC cermet is also effective for improving the stability of the power density at the constant current output. Impedance analysis suggests that the improvement of anodic activity by mixing Ni with GDC was brought about by decreasing the diffusion overpotential, which was a result of the enlarged effective electrode area..
470. Shogo Matsubara, Shinichiro Kaneko, Shinji Morimoto, Shoichi Shimizu, Tatsumi Ishihara, Yusaku Takita, Practical capacitive type CO2 sensor using CeO2/BaCO3/CuO ceramics, IMCS-7: 7th International Meeting on Chemical Sensors Sensors and Actuators, B: Chemical, 10.1016/S0925-4005(99)00407-4, 65, 1, 128-132, 2000.06, A practical capacitive type CO2 sensor composed of CeO2/BaCO3/CuO mixed oxides has been developed for the IAQ (indoor air quality) monitoring system. Sensing detectors were fabricated as follows. The pressed pellets of CeO2/BaCO3/CuO mixed oxides were sintered at 800-900 °C for 5 h, then RuO2 electrode was formed on both sides of the pellets. In order to study CO2 sensing characteristics, the capacitance of detector was measured at 550 °C with an LCR meter. The sensitivity of Cat2%CO(2)/Cin-air was measured to be -2.5 dB. They showed good stability in CO2 sensitivity at 85 °C and 90% RH test for 1500 h. The sensor unit with an oscillation circuit using this detector was developed, and its monitoring characteristics were studied. It was shown that the sensitivity change was negligible between 0% RH and 60% RH at 30 °C. The measurement error of CO2 sensor was within 200 ppm in the humidity range of 40-90% RH, and within 30 ppm/°C in the temperature range of 5-50 °C. A CO2 concentration profile monitored in an office by the developed sensor unit showed good agreement with that monitored by an NDIR type sensor. These results suggest that the developed CO2 sensor unit may be applicable to indoor quality monitoring systems. The alumina substrate, which integrates the sensing detector of 1.6*1.2*0.5 mm3 and the printed-film heater, is small (3.6*2.8*0.4 mm3) and need no damp proofing, so that small size and low cost of the sensor can be easily attained..
471. Tatsumi Ishihara, Hiroki Fujita, Hiroyasu Nishiguchi, Yusaku Takita, SrSnO3-WO3 as capacitive-type nitrogen oxide sensor for monitoring at high temperature, IMCS-7: 7th International Meeting on Chemical Sensors Sensors and Actuators, B: Chemical, 10.1016/S0925-4005(99)00416-5, 65, 1, 319-324, 2000.06, Capacitive-type NO sensor, which is operable at high temperature, was investigated in this study for monitoring NO in flue gases from a gasoline engine. Oxide capacitor consisting of BaSnO3 or SrSnO3 mixed with WO3 exhibits high sensitivity at temperature higher than 773 K. In particular, mixed oxide capacitor of SrSnO3-WO3 exhibited high sensitivity to NO and stable response at high temperatures. Furthermore, the capacitance of SrSnO3-WO3 is less sensitive to CO2, H2O, and CO compared to NO. Addition of small amount of Pt was effective for improving the response characteristics. Consequently, mixed oxide of SrSnO3-WO3 is as promising as the capacitive-type NO sensor operable at high temperatures. The NO adsorption state was further investigated with TPD measurement. It became clear that NO adsorbed on SrSnO3 was undissociative and two adsorption species exist. In contrast, NO adsorption on WO3 is dissociative. Addition of Pt was effective for decreasing the desorption temperature of oxygen from WO3 which was formed by the dissociative adsorption of NO..
472. Tatsumi Ishihara, Kazumi Kamakura, Hiroyasu Nishiguchi, Yusaku Takita, Simultaneous detection of nitric oxide concentration and temperature using a single sensor element of SrSnO3-Fe2O3 oxide mixture, Electrochemical and Solid-State Letters, 10.1149/1.1391014, 3, 5, 245-247, 2000.05, Simultaneous detection of NO concentration and temperature by a single sensor element was investigated. Resistance of the mixed oxide of 20SrSnO3-80Fe2O3 was independent of gas, but decreased linearly with increasing temperature. However, capacitance of 20SrSnO3-80Fe2O3 decreased with increasing NO concentration, although it was hardly changed upon exposure to CO and CH4 and not significantly changed by CO2 and H2O. Therefore, NO concentration and operating temperature of sensors can be estimated simultaneously by monitoring the capacitance and the resistance of the 20SrSnO3-80Fe2O3 mixed oxide. It is expected that the sensitive detection of NO can be achieved by the simultaneous detection of NO and temperature using 20SrSnO3-80Fe2O3, since capacitance was strongly affected by temperature..
473. Yusaku Takita, Hironori Wakamatsu, Gong Liang Li, Yoshihiko Moro-Oka, Hiroyasu Nishiguchi, Tatsumi Ishihara, Decomposition of chlorofluorocarbons over metal phosphate catalysis. II. Origin of the stability of AlPO4 and the location of CE as a promoter, Journal of Molecular Catalysis A: Chemical, 10.1016/S1381-1169(99)00324-6, 155, 1-2, 111-119, 2000.04, Aluminum-phosphate catalysts prepared from aqueous solution of Al(NO3)36H2O and H3PO4 in acidic condition are effective for hydrolysis of CCl2F2. Active species of the AlPO4 catalysts were studied and it was found that not Al(PO3)3 but pure AlPO4 was active. AlPO4 was amorphous when calcined at 1000°C for 5 h. But a slight crystallization of AlPO4 took place after the reaction at 400°C for 1000 h. Crystallization of AlPO4 proceeded only in the presence of both CCl2F2 and water vapor. Replacement of 5-10 at.% of Al in AlPO4 by Ce increased the catalytic activity without changing the selectivity. The Ce-promoted catalysts were composed of the mixture of AlPO4 and CePO4. The compositions of the catalysts were the same as those of parent liquor in preparation and it was almost uniform in the surface and the bulk. AlPO4 in the Ce-promoted AlPO4 catalyst was partially crystallized after the calcination at 1000°C for 5 h. (C) 2000 Elsevier Science B.V..
474. Tatsumi Ishihara, Takaaki Shibayama, Miho Honda, Hiroyasu Nishiguchi, Yusaku Takita, Intermediate temperature solid oxide fuel cells using LaGaO3 electrolyte II. Improvement of oxide ion conductivity and power density by doping Fe for Ga site of LaGaO3, Journal of the Electrochemical Society, 10.1149/1.1393358, 147, 4, 1332-1337, 2000.04, Effects of small amounts of Fe doping for Ga site in LaGaO3-based oxide on oxide ion conductivity is investigated in this study. It is found that doping a small amount of Fe is effective for improving the oxide ion conductivity in La0.8Sr0.2Ga0.8Mg0.2O3 (LSGM). The highest oxide ion conductivity was exhibited at x = 0.03 in La0.8Sr0.2Ga0.8Mg0.2-xFexO3 among the Fe-doped samples. Electron spin resonance (ESR) measurements suggest that Fe is trivalent in LaGaO3 lattice. The application of the Fe-doped LaGaO3-based oxide for the electrolyte of solid oxide fuel cell was further investigated. Power density of the solid oxide fuel cell was increased by using Fe-doped LSGM for electrolyte. This can be explained by the decrease in electrical resistance loss by improving the oxide ion conductivity. A maximum power density close to 700 mW/cm2 was obtained at 1073 K on the cell using 0.5 mm thick La0.8Sr0.2Ga0.8Mg0.17Fe0.03O3 (LSGMF) and O2 as the electrolyte and the oxidant, respectively. Therefore, close to the theoretical open-circuit potential was exhibited by the LSGMF cell. On the other hand, the power density was slightly smaller than that of the cell using Co-doped LSGM as electrolyte, especially, at temperatures lower than 973 K. This may result from the large activation energy for ion conductivity. However, the power density of the LSGMF cell was higher than that of the LSGM cell. Therefore, LSGM doped with a small amount of Fe is a promising electrolyte similar to Co-doped LSGM for the intermediate solid oxide fuel cell..
475. Yusaku Takita, Hironori Wakamatsu, Masami Tokumaru, Hiroyasu Nishiguchi, Masami Ito, Tatsumi Ishihara, Decomposition of chlorofluorocarbons over metal phosphate catalysts III. Reaction path of CCl2F2 decomposition over AlPO4, Applied Catalysis A: General, 10.1016/S0926-860X(99)00353-1, 194, 55-61, 2000.03, Decomposition of CCl4, CCl2F2, CClF3, and CF4 was studied in the presence of water vapor over AlPO4. They began to decompose at about 300, 330, 450, and 550°C, respectively. A good linear relationship between the reactivity of CFCs and the bond dissociation energy of the C-Cl bond suggests that the C-Cl bond cleavage is the rate-determining step. The lattice structure of AlPO4 before reaction was slightly distorted but the environment of Al and P ions became uniform after the reaction, consistent with a slight progress of crystallization of AlPO4. Supporting AlPO4 onto active charcoal is not preferable to the support because of its reactivity to water vapor. ALPO-5 was less active than that AlPO4 because the inside of the pores of ALPO-5 is hydrophobic and not effective for the CCl2F2 decomposition. Meso-porous AlPO4 showed almost the same activity with AlPO4, but the destruction of the meso-porous structure brought about a loss of activity at 400°C..
476. Tatsumi Ishihara, Toshiaki Takagi, Masami Ito, Hiroyasu Nishiguchi, Yusaku Takita, CO2 sensing property of CuO-BaTiO3 mixed oxide film prepared by self-assembled multibilayer film as a precursor, Journal of Electroceramics, 10.1023/A:1009932414244, 4, 1, 207-214, 2000.01, Preparation of CuO-BaTiO3 mixed oxide thin film by the decomposition of a self-assembled multibilayer film as a molecular template was investigated in this study. Furthermore, CO2 sensing property of the resultant thin film was investigated as a capacitive type sensor. The self-assembled bilayer film of few 1000 layers thickness can be obtained easily by casting an aqueous suspension consisting of dimethyldihexadecylammoiun bromide (DCl-16), Cu(ClO4)2, Ba(TiO(C2H4)2), 2,6-dimetyle-3,5heptadione (DHP), and polyvinyl alcohol. Divalent copper ion (Cu2+) which is associated with 2 DHP molecules was incorporated into the molecular bilayer film and BaTiO3 precursor exists at the interspace of molecular bilayer film by coordinating with polyvinyl alcohol. Upquenching the organic-inorganic film at 1173 K leads to the uniform film of CuO-BaTiO3 oxide mixture. Although operating temperature shifted to higher temperature, the resultant film exhibits the capacitance change upon exposure to CO2. Consequently, it is concluded that the mixed oxide film of CuO-BaTiO3 prepared by the decomposition of multibilayer film was also an appropriate capacitive type CO2 sensor..
477. Akira Ninomiya, Misuzu Sato, Toshio Muraya, Tatsumi Ishihara, Yusaku Takita, A novel catalytic process for SNG synthesis, Nippon Kagaku Kaishi / Chemical Society of Japan - Chemistry and Industrial Chemistry Journal, 4, 1999.12, Methane rich city gas has been synthesized by means of steam retorming of naphtha; however, the produced gas always contains significant concentration of CO and CO2. Therefore, development of a methane production process containing no CO and CO2 removal processes is strongly requested. Authors reported in the previous paper that C3H8→2CH4+C(1) took place over Ni/SiO2 with 90% selectivity. In this paper, the catalyst supports were studied and found that neutral SiO2 and α-Al2O3 are suitable but the activity was much reduced over Ni supported on acidic SiO2-Al2O3. Catalyst was diluted by various materials to avoid blocking-up by the deposited carbon. Several diluted materials affected the conversion, α-Al2O3 and basic MgO accelerated the reaction which may be due to interaction between Ni and dilution materials with direct contact. Over Ni/SiO2, reaction (1) took place with 90% selectivity, so that the produced gas always contained H2 formed by the C3H8→3C+4H2(2). It has confirmed that H2 in a high concentration of CH4 can be reacted with C3H8 to produce CH4. From these results, a following simple synthesis process can be constituted; the first step is CH4, H2, and solid C formation from C3H8, and the second step is succeeding H2 consumption process of the produced gas in the first step..
478. Tatsumi Ishihara, Haruyoshi Furutani, Improved oxide ion conductivity in La0.8Sr0.2Ga0.8Mg0.2O3 by doping Co, Chemistry of Materials, 11, 8, 2081-2088, 1999.12, The effects of doping Co for the Ga site on the oxide ion conductivity of La0.8Sr0.2Ga0.8-Mg0.2O3 have been investigated in detail. It was found that doping Co is effective for enhancing the oxide ion conductivity. In particular, a significant increase in conductivity in the low-temperature range was observed. The electrical conductivity was monotonically increased; however, the transport number for the oxide ion decreased with an increasing amount of Co. Considering the transport number and ion transport number, an optimized amount for the Co doping seems to exist at 8.5 mol % for Ga site. The theoretical electromotive forces were exhibited on H2-O2 gas cell utilizing the optimized composition of La0.8Sr0.2-Ga0.8Mg0.115Co 0.085O3. The diffusion characteristics of the oxide ion in La0.8Sr0.2Ga0.8Mg0.115-Co 0.085O3 were also investigated by using the 18O tracer method. Since the diffusion coefficient measured by the 18O tracer method was similar to that estimated by the electrical conductivity, the conduction of La0.8Sr0.2Ga0.8Mg0.115Co 0.085O3 is concluded to be almost ionic. On the other hand, an oxygen permeation measurement suggests that the oxide ion conductivity increased linearly with an increasing amount of Co. Therefore, specimens with Co content higher than 10 mol % can be considered as a superior mixed oxide ion and hole conductor. The UV-vis spectra suggests that the valence number of doped Co was changed from +3 to +2 with decreasing oxygen partial pressure; the origin of hole conduction can thus be assigned to the formation of Co3+. Since the amount of dopant in the Ga site was compensated with Mg2+, the amount of oxygen deficiency was decreased by doping Co. Therefore, it is likely that the improved oxide ion conductivity observed by doping with Co is brought about by the enhanced mobility of oxide ion..
479. Yusaku Takita, Maiko Ninomiya, Hidenori Miyake, Hironori Wakamatsu, Yusuke Yoshinaga, Tatsumi Ishihara, Catalytic decomposition of perfluorocarbons. Part II. Decomposition of CF4 over AlPO4-rare earth phosphate catalysts, Physical Chemistry Chemical Physics, 10.1039/a904311j, 1, 18, 4501-4504, 1999.09, Catalytic activity of various metal phosphates were studied and it was found that Zr and Al phosphates are effective for CF4 decomposition in the presence of water vapor at above 600 °C and the specific surface areas of these active catalysts were remarkably large after calcination at 1000 °C for 5 h. No CF4 decomposition took place up to 700 °C over the Mg2P2O7, Ca2P2O7, BPO4, FePO4 or the BiPO4 catalysts. The catalysts prepared from the solutions containing Al and rare earth (RE) nitrates and phosphoric acid are mixtures of the ALPO4 and RE phosphates. The mixtures of ALPO4 and phosphates of Y, La, Ce, Pr, Nd, and Gd increased in activity. Heavy rare earth elements (Er and Yb) showed little promotion effects. The catalytic activity of the Ce10%-AlPO4 slightly declined within the initial 40 h and then reached a steady value. 4.2 mol% of water vapor in the feed is sufficient for CF4 decomposition over Ce10%-AlPO4..
480. M. Kagawa, H. Nishiguchi, T. Ishihara, Y. Takita, Selective reduction of NO over cobalt phosphate catalyst with C3H6 or CH4, Sekiyu Gakkaishi (Journal of the Japan Petroleum Institute), 10.1627/jpi1958.42.258, 42, 4, 258-265, 1999.07, A study of the activity of metal phosphate catalyst in selective reduction of NO with propene showed that Co3(PO4)2 and GaPO4 exhibited high catalytic activities, with the former catalyst exhibiting the highest activity. The selective reduction of NO hardly proceeded when methane was used as reductant. However, the loading of Pt on Co3(PO4)2 was found to be effective for enhancing the activity in this reaction. TPD techniques were used to further study the reaction mechanism in NO reduction over Co3(PO4)2 catalyst. NO-TPD and NO direct decomposition results suggested that N2 was formed by the dissociative adsorption of NO which is the initial reaction step in NO reduction, however, the adsorption of oxygen on this catalyst was very strong to desorb. Propene as a reductant was considered effective in removing surface oxygen formed by NO decomposition. This study revealed that Co3(PO4)2 is highly active and selective in NO reduction with hydrocarbon in the presence of oxygen. Co3(PO4)2 shows potential as a thermostable de-NOx catalyst for lean combustion engines as its thermal stability is sufficient to meet practical applications..
481. Tatsumi Ishihara, Takaaki Shibayama, Miho Honda, Hiroyasu Nishiguchi, Yusaku Takita, Solid oxide fuel cell using Co doped La(Sr)Ga(Mg)O3 perovskite oxide with notably high power density at intermediate temperature, Chemical Communications, 10.1039/a902899d, 13, 1227-1228, 1999.07, Power generation characteristics of fuel cells was greatly improved by using La0.8Sr0.2Ga0.8Mg0.115Co0.085O3 as electrolyte. In particular, the maximum power density attained a value of 1.53 and 0.50 W cm-2 at 1073 and 873 K, respectively, in an H2-O2 cell when the thickness of electrolyte was 0.18 mm..
482. Yusaku Takita, Maiko Ninomiya, Rie Matsuzaki, Hironori Wakamatsu, Hiroyasu Nishiguchi, Tatsumi Ishihara, Decomposition of chlorofluorocarbons over metal phosphate catalysts part I. Decomposition of CCI2F2 over metal phosphate catalysts, Physical Chemistry Chemical Physics, 10.1039/a809967g, 1, 9, 2367-2372, 1999.05, In the decomposition of chlorofluorocarbons (CFCs), HF produced in the decomposition reacts with and deactivates the catalyst. Metal phosphates were chosen as the catalyst from ΔG calculations. Zr-P-O and AlPO4 showed high catalytic activity for the decomposition of CCl2F2 above 350°C. The essential reaction of the decomposition is hydrolysis. On increasing the CCl2F2 concentration in the feed, the formation of CClF3 as a by-product is promoted. ALPO4 has both weak acid sites and those of intermediate strength and these acid sites may participate in the hydrolysis of CCl2F2. No reaction between AlPO4 and formed HF was observed during 1000 h reaction at 400°C, ALPO4 promises to be of practical use..
483. Tatsumi Ishihara, Haruyoshi Furutani, Hiroshi Arikawa, Miho Honda, Taner Akbay, Yusaku Takita, Oxide ion conductivity in doubly doped PrGaO3 perovskite-type oxide, Journal of the Electrochemical Society, 10.1149/1.1391820, 146, 5, 1643-1649, 1999.05, In this study, oxide ion conduction characteristics of doubly doped PrGaO3 were investigated. It is found that PrGaO3 doped with Sr (or Ca) for the Pr site and Mg for the Ga site exhibits the high oxide ion conduction which was slightly less than that measured for doubly doped La(Sr)Ga(Mg)O3 (LSGM). Doping alkaline earth cations for the Pr site and Mg for the Ga site of the PrGaO3 increased its oxide ion conductivity. For temperatures above 1073 K, the highest oxide ion conductivity was obtained for the composition of Pr0.93Sr0.07Ga0.85Mg0.15O3 (PSGM). On the other hand, the apparent activation energy of Pr0.93Ca0.07Ga0.85M0.15O3 (PCGM) was as low as 0.65 eV. Therefore, the electrical conductivity of PCGM was higher than that of LSGM at temperatures below 873 K. Although hole conduction was observed, electron conductivity of the doubly doped PrGaO3 was almost independent of the oxygen partial pressure from pO(2) = 1 to 10-21 atm. It is clear that doped PrGaO3 is a new fast oxide ion conductor over a wide range of oxygen partial pressures. On the other hand, a nonlinearity was observed on the Arrhenius plot of electrical conductivity for Ca-doped PrGaO3 and the high temperature X-ray diffraction (XRD) measurement suggested that it was due to phase transition from orthorhombic to rhombohedral or tetragonal, which may decrease the mobility of oxide ions. Application of PSGM and PCGM for an electrolyte of solid oxide fuel cell was also investigated in order to cross-check the findings of the fast oxide ion conductivity. This study revealed that PSGM and PCGM were a new family of fast oxide ion conductors..
484. Tatsumi Ishihara, Takashi Yamada, Taner Akbay, Yusaku Takita, Partial oxidation of methane over fuel cell type reactor for simultaneous generation of synthesis gas and electric power, Proceedings of the 1999 1st International Symposium on Multifunctional Reactors Chemical Engineering Science, 10.1016/S0009-2509(99)00052-4, 54, 10, 1535-1540, 1999.05, A novel solid oxide fuel cell (SOFC) type catalytic reactor utilizing partial oxidation of methane (CH4 + 1/2O2 = CO+2H2) as internal reforming reaction was investigated in the present study. Large electric power, CO-H2 mixture with molar ratio of 2, and heat energy were obtained simultaneously by applying LaGaO3 based perovskite as electrolyte of fuel cells. Since LaGaO3 based oxide exhibits fast oxide ion conduction, large electric power was obtained. The electric power was further increased by doping small amount of Co or Fe, whilst the open circuit potential decreased due to hole conduction. In spite of 0.5 mm thickness of electrolyte, a maximum power density and yield of synthesis gas were obtained at 731 mW/cm2 and 21 % at 1273 K respectively on the cell for which Fe doped LaGaO3 based oxide was used. In addition, partial oxidation of methane only occurred in the cell, since the molar ratio of formed CO and H2 was always 1/2. Therefore, partial oxidation of methane with SOFC is highly attractive from simultaneous generation of energy and useful compound..
485. Y. Takita, A. Ninomiya, M. Sato, T. Ishihara, A novel catalytic process for SNG synthesis, NIPPON KAGAKU KAISHI, 2000, 4, 237-243, 1999.04, The catalyst supports were studied for the reaction C3H8 → 2CH4 + C (reaction 1). Neutral SiO2 and α-Al2O3 were found suitable while the acidic SiO2-Al2O3 support significantly reduced the activity of Ni catalyst. The catalyst was diluted by various materials to avoid its blocking up by carbon deposition. Some diluting materials affected the conversion. α-Alumina and basic MgO accelerated the reaction which may be due to the interaction between nickel and diluting materials through direct contact. Over Ni/SiO2, the reaction 1 showed 90% selectivity, so that the produced synthetic natural gas always contained H2 formed in the reaction C3H8 → 3C + 4H2..
486. Akira Ninomiya, Misuzu Sato, Hiroyasu Nishiguchi, Tatsumi Ishihara, Yusaku Takita, Atmospheric Production Process for Substitute Natural Gas from Saturated Hydrocarbons 1. Utilization of Catalytic Reaction for Atmospheric Methane Formation, kagaku kogaku ronbunshu, 10.1252/kakoronbunshu.25.316, 25, 2, 316-321, 1999.01, In order to develop a novel production process for substitute natural gas (SNG), SiO2-supported metal catalysts effective for methane formation from propane and butanes are investigated under atmospheric pressure. Two reactions, namely, methane formation, C3H8→2 CH4+C, and decomposition, C3H8→3C+4H2, took place over the analyzed metal supported catalysts. The highest activity is measured for Ni/SiO2, revealing 100% conversion and over 90% selectivity for methanation at 500° C. As far as the activities of other metal supports are concerned, the order is found to be Ni»Co>Fe> Pt>Pd. Butanes show 95~99 % conversion and 80% selectivity over Ni/SiO2 at 500°C. Adopting the condition of less than 2, 700h-1 is found suitable for selective CH4 formation. Supplying the feed of C3 H8/H2=0.5, only hydrogenolysis of propane takes place over Ni/SiO2 above 250°C, and the conversion reachs 90% and 100% at 350°C and 500°C, respectively..
487. Yusaku Takita, Chiharu Morita, Maiko Ninomiya, Hironori Wakamatsu, Hiroyasu Nishiguchi, Tatsumi Ishihara, Catalytic decomposition of CF4 over AIPO4-based catalysts, Chemistry Letters, 10.1246/cl.1999.417, 5, 417-418, 1999.01, The most stable perfluorocarbon, CF4, was decomposed to CO2 at above 550 °C in the presence of water vapor over AIPO4 in which 10 atomic % of A1 ions are substituted by Ce Catalytic activity slightly decreased within first 50 h and then took a stationary state for succeeding 50 h. No changes in the structure of catalyst were observed after 100 h reaction. Mg pyrophosphate and phosphates of Ca, B, Fe, Zn, Bi, and Ni were not active up to 700 °C. The addition of Ce, La, Pr, Nd, Gd, Yb, Er, or Y into AIPO4 increased the catalytic activity..
488. Tatsumi Ishihara, Hiroyasu Nishiguchi, Keiko Fukamachi, Yusaku Takita, Effects of acceptor doping to KTaO3 on photocatalytic decomposition of pure H2O, Journal of Physical Chemistry B, 103, 1, 1-3, 1999.01, It was found for the first time that controlling the charge density in oxide semiconductors with an acceptor was effective for improving the activity to photolysis of H2O. Although the photodecomposition activity of NiO supported on nondoped KTaO3 was negligibly small, doping small amount of acceptors such as tri- or tetravalent cations to KTaO3 increased the formation rate of H2 and O2. In particular, it was found that NiO supported on KTaO3 doped with 8 mol % Zr4+ exhibits higher activity to the photocatalytic decomposition of H2O than that of a well-known photocatalyst of PtTTiO2 ..
489. Hiroshi Arikawa, Takashi Yamada, Tatsumi Ishihara, Hiroyasu Nishiguchi, Yusaku Takita, Mixed electronic-oxide ionic conductivity and oxygen permeating property in Ni doped LaGaO3 perovskite oxide, Chemistry Letters, 10.1246/cl.1999.1257, 12, 1257-1258, 1999.01, It was found that LaGaO3 perovskite oxide doped with Ni for Ga site exhibits a high mixed electronic-oxide ionic conduction. Oxygen permeation rate was increased with increasing Ni content and it attained to a maximum value of 2.15 cm3/min cm2 at 1273 K when 25 mol% Ni was doped..
490. Chiemi Mitsui, Hiroyasu Nishiguchi, Keiko Fukamachi, Tatsumi Ishihara, Yusaku Takita, Photocatalytic decomposition of pure water over NiO supported on KTa(M)O3 (M=Ti4+,Hf4+,Zr4+) perovskite oxide, Chemistry Letters, 10.1246/cl.1999.1327, 12, 1327-1328, 1999.01, Photocatalytic decomposition of pure water on NiO supporting KTaO3 partially substituted with acceptor was investigated. Formation rate of H2 and O2 increased by partially substituting Ta with group 4 element. The increased photocatalytic decomposition activity by additives might be caused by a charge carrier annihilation..
491. Tatsumi Ishihara, Takaaki Shibayama, Miho Honda, Hiroyasu Nishiguchi, Yusaku Takita, Transition metal doped LaGaO perovskite fast oxide ion conductor and intermediate temperature solid oxide fuel cell, Unknown Journal, 575, 283-294, 1999.01, Doping transition metal cation is known to enhance the electric conduction of solid electrolytes, however, the ionic conduction can be improved by doping the small amount of transition metal, in particular, doping Co is effective for improving the oxide ion conductivity. In this investigation, oxide ion conductivity of LaGaO3 based oxide doped with Co were investigated in detail. It was found that LaGaO3 doped with Co for Ga site (LSGMC) show a notable oxide ion conductivity over a wide range of oxygen partial pressures, although a hole conduction was appeared by addition of excess amount of Co. Considering the electrical conductivity and transport number of oxide ion, the optimized composition of LSGMC seems to be existed at La0.8Sr0.2Ga0.8Mg0.115Co 0.085O3. Power generation characteristics of fuel cells was greatly improved by using LSGMC for electrolyte and extremely large power density can be obtained on both H2-O2 and H2-air cells. In particular, the maximum power density was attained to a value of 1.53and 0.50 W/cm2 at 1073 and 873 K, respectively, on H2-O2 cell when the thickness of electrolyte was 0.18 mm. Furthermore, almost similar large power density was attained when air was used as oxidant. The high power density of cell demonstrated in this study suggests that the operating temperature of SOFC can be decreased by using LSGMC for electrolyte..
492. Tatsumi Ishihara, Shogo Matsubara, Capacitive type gas sensors, Journal of Electroceramics, 10.1023/A:1009970405804, 2, 4, 215-228, 1998.12, Current status of capacitive type gas sensor were reviewed in this paper. Although the number of publications on capacitive type sensors has been limited so far, capacitive type sensors have good prospects given that the capacitor structure is so simple enabling miniaturization and achieving high reliability and low cost. Among the reported capacitive type sensors, detection of gas based on a change in dielectric layer thickness is most promising. On this point of view, capacitive type CO2 and NO sensors using depletion layer formed at p-n junction of oxide semiconductor were introduced in detail. In addition, commercial capacitive type sensors for monitoring CO2 based on this principle were mentioned. CO2 concentration in office can be successfully monitored by the developed capacitive type CO2 sensor..
493. Tatsumi Ishihara, Taner Akbay, Haruyoshi Furutani, Yusaku Takita, Improved oxide ion conductivity of Co doped La0.8Sr0.2Ga0.8Mg0.2O3 perovskite type oxide, Solid State Ionics, 113-115, 585-591, 1998.12, Effects of doping certain transition metal cations for the Ga site on the oxide ion conductivity of La0.8Sr0.2Ga0.8Mg0.2O3 has been investigated in detail. It was found that doping with Co is effective for enhancing the oxide ion conductivity. In particular, a significant increase at low temperature was observed. Electrical conduction can generally be improved by doping transition metal cations, however, the theoretical emf was almost exhibited in an H2-O2 cell utilizing Co doped La0.8Sr0.2Ga0.8Mg0.2O3 for Co concentrations lower than 10 mol% on the Ga site. Diffusion characteristics of the oxide ion in La0.8Sr0.2Ga0.8Mg0.5Co0.085O 3 has also been investigated by using the 18O tracer method. Since the diffusion coefficient measured by the 18O tracer method is almost the same as that the one estimated via electrical conductivity measurements, it was concluded that the conduction of La0.8Sr0.2Ga0.8Mg0.115Co 0.085O3 is almost ionic. It seems most likely that the improved oxide ion conductivity by doping with Co is brought about by the enhanced mobility of the oxide ions..
494. Tatsumi Ishihara, John A. Kilner, Miho Honda, Natsuko Sakai, Harumi Yokokawa, Yusaku Takita, Oxygen surface exchange and diffusion in LaGaO3 based perovskite type oxides, Solid State Ionics, 113-115, 593-600, 1998.12, Isotopic exchange was used to determine the oxygen tracer diffusion coefficient and surface exchange coefficient of LaGaO3 based perovskites at a temperature from 923 to 1173 K. The oxygen diffusion coefficient was found to be higher than the surface exchange coefficient. In addition, the change in activation energy of the surface exchange coefficient was also observed at 973 K. The results indicate that the oxygen exchange behavior of acceptor doped LaGaO3 is similar to that of other oxygen ion conductors such as ZrO2-Y2O3 and CeO2-Gd2O3, rather than that was found for the isostructural, but mainly mixed conducting, perovskite oxides. It was noted that the diffusion coefficient was not influenced while the surface exchange coefficient was strongly affected by the oxygen partial pressure of isotopic exchange and the empirical relation was found to be a power of 0.45. Oxygen tracer diffusion data obtained by SIMS was compared to that obtained by the measurement of the electrical conductivity with the Nernst-Einstein relationship. For the temperatures at which the measurements were taken, the two were almost identical within the accuracy of SIMS, strongly indicating that the conductivity in LSGM is ionic. The high oxide ion conductivity in LSGM results from the high mobility of oxygen vacancies in addition to the high concentration of oxygen vacancies..
495. Takashi Yamada, Yoshiko Hiei, Taner Akbay, Tatsumi Ishihara, Yusaku Takita, Simultaneous generation of synthesis gas and electric power by internal reforming fuel cells utilizing LaGaO3 based electrolytes, Solid State Ionics, 10.1016/s0167-2738(98)00289-6, 113-115, 253-258, 1998.12, A novel solid oxide fuel cell (SOFC) utilizing partial oxidation of methane (CH4 + 1/202 = CO + 2H2) as internal reforming reaction was investigated in the present study. Large electric power as well as CO-H2 mixture with molar ratio of 2 were obtained by applying LaGaO3 perovskite as electrolyte. Although the open circuit potential decreased, the maximum power density increased by doping a small amount of Co to the LaGaO3 electrolyte. In particular, the increase in the power density at 1073 K was significant. Increasing the amount of doped Co monotonically enhanced the hole conduction resulting in a decrease in the open circuit potential and an increase on the amount of leaked oxygen which results in diminished electric power. Consequently, it became clear that the optimized composition for this electrolyte was La0.9Sr0.1Ga0.8Mg0.115Co 0.085O3 considering the power density and the amount of oxygen leakage. Although the thickness of electrolyte with the above composition was as thick as 0.5 mm, a maximum power density and yield of synthesis gas were obtained at 242 mW/cm2 and 16%, respectively at 1073 K..
496. T. Ishihara, M. Honda, T. Shibayama, H. Furutani, Y. Takita, An intermediate temperature solid oxide fuel cell utilizing superior oxide ion conducting electrolyte, doubly doped LaGaO3 perovskite, Ionics, 10.1007/BF02375883, 4, 5-6, 395-402, 1998.09, LaGaO3-based perovskite oxide doped with Sr and Mg exhibits high ionic conduction over a wide oxygen partial pressure. In this study, the stability of the LaGaO3 based oxide was investigated. It became clear that LaGaO3 based oxide is very stable for reduction and oxidation. SOFCs utilizing LaGaO3-based perovskite type oxide for electrolyte were further studied for the decreased temperature solid oxide fuel cells. The power generation characteristics of cells were strongly affected by the electrode, both anode and cathode. It became clear that Ni and LnCoO3 (Ln: rare earth) are suitable for anode and cathode, respectively. Rare earth cations in the Ln-site of Cobased perovskite cathode also have a great effect on the power generation characteristics. In particular, high power density could be attained in the temperature range from 973 to 1273 K by using doped SmCoO3 for the cathode. The electrical conductivity of SmCoO 3 increases with increasing Sr amount doped for the Sm site and attained the maximum at Sm0.5Sr0.5CoO3. The cathodic overpotential and the internal cell resistance exhibit almost opposite dependence on the amount of doped Sr. Consequently, the power density of the cell reaches a maximum when Sm0.5Sr0.5CoO3 is used for cathode. On this cell, the maximum power density is as high as 0.58 W/cm2 at 1073 K, although a 0.5 mm thick electrolyte is used. Therefore, this study reveals that the LaGaO3 based oxide for electrolyte and the SmCoO3 based oxide for cathode are promising for solid oxide fuel cells at intermediate temperature..
497. Tatsumi Ishihara, Hiroki Fujita, Yusaku Takita, Effects of Pt addition for SrSnO3-WO3 capacitive type sensor on NO detection at high temperature, Sensors and Actuators, B: Chemical, 10.1016/S0925-4005(98)00263-9, 52, 1-2, 100-106, 1998.09, A capacitive type NO sensor which is operable at high temperature and under low oxygen partial pressure has been investigated in this study for monitoring NO in exhaust gases from gasoline engine vehicles. It was found that a mixed oxide of SrSnO3 and WO3 exhibited the high sensitivity at temperatures higher than 773 K. However, the SrSnO3-WO3 capacitor required a long period to response and recovery even at temperatures higher than 773 K. Improvement of the response characteristics was further studied and it became clear that addition of Pt was effective for improving the response and recovery behavior. In particular, loading Pt to WO3, followed by mixing with SrSnO3, was effective for improving the response characteristics without decreasing the sensitivity at high temperatures. On the mixed oxide of SrSnO3-(Pt/WO3), the 90% response and recovery to 100 ppm NO were attained within 6.5 and 1.0 min, respectively. Furthermore, the capacitance of SrSnO3-(Pt/WO3) increased with increasing NO concentrations in the range of 10 to a few 100 ppm. In addition, SrSnO3-(Pt/WO3) was less sensitive to H2O, CO, CO2 and NO2 than that to NO. Therefore, the mixed oxide capacitor of SrSnO3-(Pt/WO3) was usable for monitoring NO at high temperature and low oxygen partial pressure. Effects of Pt addition on the equivalent circuit of the sensor element was further investigated with the impedance measurement. Addition of Pt increased the interface resistance of the mixed oxide. However, the electrical equivalent circuit was not changed by the Pt doping. Therefore, improved response characteristics seem to be assigned to acceleration in the surface nitration reaction by gaseous NO with the Pt addition..
498. P. R. Slater, J. T.S. Irvine, T. Ishihara, Y. Takita, High-Temperature Powder Neutron Diffraction Study of the Oxide Ion Conductor La0.9Sr0.1Ga0.8Mg0.2O2.85, Journal of Solid State Chemistry, 10.1006/jssc.1998.7821, 139, 1, 135-143, 1998.08, Powder neutron diffraction data have been collected between room temperature and 1000°C for the oxide ion conductor La0.9Sr0.1Ga0.8Mg0.2O 2.85and the undoped parent phase LaGaO3. In agreement with previous studies, refinement of the data for the undoped phase showed that the cell is orthorhombic (Pbnm) at room temperature and rhombohedral (R3c) between 250 and 1000°C. The structure of the doped system La0.9Sr0.1Ga0.8Mg0.2O 2.85is, however, significantly different from that of pure LaGaO3. The room temperature structure is monoclinic (I2/a), and there appear to be two phase transitions between 250 and 1000°C: monoclinic (pseudo-orthorhombic)→monoclinic (pseudo-rhombohedral)→rhombohedral. Significant changes are also seen in the GaO6octahedra on doping LaGaO3. In particular, the octahedra are substantially more distorted in the doped phase. The tilting of the octahedra is smaller for the doped phase and the degree of tilting is reduced as the temperature is raised. Possible correlation between the tilting of the octahedra and the activation energy for oxide ion conduction is presented..
499. Gong Liang Li, Hiroyasu Nishiguchi, Tatsumi Ishihara, Yoshihiko Moro-Oka, Yusaku Takita, Catalytic dehydrofluorination of CF3CH3(HFC143a) into CF2CH2(HFC1132a), Applied Catalysis B: Environmental, 10.1016/S0926-3373(97)00087-8, 16, 4, 309-317, 1998.05, The catalytic dehydrofluorination of CF3CH3 was studied over various metal phosphate catalysts in a fixed-bed reactor. The Mg2P2O7 catalyst exhibited the moderate activity and high selectivity of CF2CH2, and it is the most suitable catalyst for the dehydrofluorination of CF3CH3. Deactivation did not take place during the 100 h reaction over the Mg2P2O7 catalyst, and XRD patterns of the catalyst were unchanged after 100 h reaction. However, small amounts of F- ions were present on the surface of the catalyst from results of XPS. The active sites for CF2CH2 formation are weak acid sites of the catalysts, and carbon deposition and/or polymerization take place on strong acid sites. Results of CF3CH3-TPD indicated that the dehydrofluorination proceeds through a +CF2CH3 carbonium-ion mechanism over Mg2P2O7 catalyst, and the rate-determining step is the cleavage of the C-F bond..
500. Yusaku Takita, Ken Ichi Sano, Toshio Muraya, Hiroyasu Nishiguchi, Noboru Kawata, Masami Ito, Taner Akbay, Tatsumi Ishihara, Oxidative dehydrogenation of iso-butane to iso-butene II. Rare earth phosphate catalysts, Applied Catalysis A: General, 10.1016/S0926-860X(98)00043-X, 170, 1, 23-31, 1998.05, Among various rare earth phosphates, CePO4 and LaPO4 were found to catalyze the oxidative dehydrogenation of isobutane to iso-butene at 450-550°C using a feed gas of 75 mol% iso-butane and 5 mol% O2. As for the phosphates of Y, Pr, Nd, Gd, Er, and Yb, iso-butene was formed with a limited selectivity of 20-40% selectivity, and C3H6 formation and deep oxidation into CO and CO2 were promoted over the same temperature range. Temperature-programmed-desorption spectra of NH3 for CePO4 and LaPO4 consisted of two large desorption peaks with maxima at 100°C and 270°C suggesting that these phosphates have strong acid sites. But the rest of the phosphates have only weak acid sites. Rare earth phosphates have no adsorbed oxygen which can be desorbed up to 550°C. The lattice oxygen of CePO4 and PrPO4 can be reduced at 200°C and that of the rest of the phosphates at about 400°C. The amount of oxygen removed up to 550°C in TPR was smaller than the amount corresponding to a monolayer for all phosphates. Oxygen isotope equilibration experiments over CePO4 and LaPO4 revealed that only surface lattice oxygen can participate in the equilibration at 500°C and 550°C. It can be concluded that acidic character is a key factor in the selective oxidative dehydrogenation of iso-butane over the rare earth phosphate catalysts..
501. P. R. Slater, J. T.S. Irvine, T. Ishihara, Y. Takita, The structure of the oxide ion conductor La0.9Sr0.1Ga0.8Mg0.2O2.85 by powder neutron diffraction, Solid State Ionics, 107, 3-4, 319-323, 1998.04, High resolution powder neutron diffraction has shown that the room temperature structure of the new fast oxide ion conducting solid electrolyte La0.9Sr0.1Ga0.8Mg0.2O2.85 is monoclinic, rather than orthorhombic, as for the undoped parent phase LaGaO3. In both systems the main distortion of the structure from the ideal perovskite is the tilting of the GaO6 octahedra, and the symmetry change has a direct effect on this tilting, such that for LaGaO3 the [001]p tilt is in-phase when successive octahedra are considered, while for La0.9Sr0.1Ga0.8Mg0.2O2.85 it is antiphase. The degree of tilting of the octahedra is also reduced by the doping. For this room temperature data, the oxygen vacancies in La0.9Sr0.1Ga0.8Mg0.2O2.85 are shown to be preferentially located in the apical sites..
502. Yusaku Takita, Ken Ichi Sano, Kazuo Kurosaki, Noboru Kawataa, Hiroyasu Nishiguchi, Masami Ito, Tatsumi Ishihara, Oxidative dehydrogenation of iso-butane to iso-butene I. Metal phosphate catalysts, Applied Catalysis A: General, 10.1016/S0926-860X(97)00297-4, 167, 1, 49-56, 1998.02, Metal pyrophosphates catalyse the oxidative dehydrogenation of iso-butane to iso-butene at 450-550°C using a feed gas of 75 mol% iso-butane and 5% O2. Ni2P2O7 is the most selective catalyst with the iso-butene selectivity reaching to a maximum value of 82.2% at 550°C. Ag4P2O7 and Zn2P2O7 are also effective, but the iso-butene selectivities were slightly lower than that of Ni2P2O7. Pyrophosphates of Mg, Cr, Co, Mn, and Sn catalyse the oxidative dehydrogenation, but the iso-butene selectivity was 43.8-65.7% at the temperature where the maximum iso-butene yield is observed. The optimum oxygen concentration for iso-butene formation was 5-15 mol%, but the increase in O2 concentration did not increase the iso-butene selectivity. No adsorbed oxygen species was found by means of TPD. The lattice oxygen of the pyrophosphates began to react with H2 at 200-400°C. Reactivity of the lattice oxygen of pyrophosphates can be estimated from the value of ΔH0f for the corresponding oxide. More than 2 desorption peaks were observed in the TPD spectra of NH3 adsorbed on the pyrophosphates, and a linear correlation was found between the concentration of acid amount of the catalysts and the specific rate of iso-butene formation. This strongly suggests that the acidic sites play a key role in the iso-butene formation..
503. Masami Ito, Tatsumi Ishihara, Yu Saku Takita, Atmospheric CO2 fixation by dinuclear Ni(II) complex, [TPANi(II)(μ-OH)2Ni(II)TPA](ClO4)2 (TPA = Tris(pyridylmethyl)amine), Studies in Surface Science and Catalysis, 114, 499-502, 1998.01, The dinuclear Ni(II) complex [TPANi(II)(μ-OH)2Ni(II)TPA](CiO4)2 (TPA = tris(pyridylmethyl)amine) (2) can react with atmospheric CO2 readily, and forms corresponding μ-carbonate complex, [TPANi(II)(μ-CO3)Ni(II)TPA](ClO4)2 (3)..
504. Tatsumi Ishihara, Hiroki Fujita, Yusaku Takita, Capacitive type Nox sensor operable at high temperature, IEEJ Transactions on Sensors and Micromachines, 10.1541/ieejsmas.118.113, 118, 2, 113-118, 1998.01, Capacitive type NO sensor which is operable at high temperature was investigated in this study for monitoring NO in flue gases from gasoline engine vehicle. Although the high sensitivity is obtained at temperature lower than 400°C, it is negligibly small at temperature higher than 500°C on large part of the mixed oxide examined. On the other hand, BaSnO3 or SrSnO3 mixed with WO3 exhibits the high sensitivity at temperature higher than 500°C. In particular, mixed oxide capacitor of SrSnO3-WO3 exhibited the high sensitivity to NO at 550°C. Since the capacitance of this oxide increased with increasing NO concentration, in the range from 10 to few 1000 ppm. NO concentration can be evaluated with the capacitance of the element. Furthermore, the capacitance of SrSnO3 WO3 is less sensitive to CO2 H2O and CO comparing that to NO. Consequently, mixed oxide of SrSnO3-WO3 is promising for the capacitive NO sensor operable at high temperature..
505. Yusaku Takita, Tatsumi Ishihara, Catalytic decomposition of CFCs, Catalysis Surveys from Japan, 10.1023/A:1019094828720, 2, 2, 165-173, 1998.01, Catalytic decomposition of CCl2F2 was studied over a number of single and complex metal oxides using a fixed-bed reactor. The ZrO2-Cr2O3 catalyst exhibited the highest activity and CO2 and CClF3 were formed at 350 450°C. Selective decomposition of CCl2F2 into CO2 required the presence of both oxygen and water vapor over the catalyst. Catalytic activity gradually declined with time on stream because of the fluorination of ZrO2. Treatment of the catalyst with both oxygen and water vapor promoted the removal of fluoride ions in sub-surface layers of the catalyst, which is effective for the recovery of the activity. CCl2F2 was decomposed at 300-450°C over AlPO4. No fluorination of the AlPO4 catalyst took place after the reaction for 1000 h. CH2FCF3, an alternative CFC, was completely decomposed over the mixed catalyst of Ce promoted AlPO4 and Cr2O3 at 400-500°C. Catalytic decomposition is a rational method for destruction of used CFCs..
506. Tatsumi Ishihara, Miho Honda, Takaaki Shibayama, Hiroaki Minami, Hiroyasu Nishiguchi, Yusaku Takita, Intermediate temperature solid oxide fuel cells using a new LaGaO3 based oxide ion conductor, Journal of the Electrochemical Society, 10.1149/1.1838783, 145, 9, 3177-3183, 1998.01, LaGaO3-based perovskite oxides doped with Sr and Mg exhibit high ionic conductivity over a wide range of oxygen partial pressure. In this study, the stability of LaGaO3-based oxide was investigated. The LaGaO3-based oxide was found to be very stable in reducing, oxidizing, and CO2 atmospheres. Solid oxide fuel cells (SOFCs) using LaGaO3-based perovskite-type oxide as the electrolyte were studied for use in intermediate-temperature SOFCs. The power-generation characteristics of cells were strongly affected by the electrodes. Both Ni and LnCoO3 (Ln:rare earth) were suitable for use as anode and cathode, respectively. Rare-earth cations in the Ln site of the Co-based perovskite cathode also had a significant effect on the power-generation characteristics. In particular, a high power density could be attained in the temperature range 973-1273 K by using a doped SmCoO3 for the cathode. Among the examined alkaline earth cations, Sr-doped SmCoO3 exhibits the smallest cathodic overpotential resulting in the highest power density. The electrical conductivity of SmCoO3 increased with increasing Sr doped into the Sm site and attained a maximum at Sm0.5Sr0.5CoO3. The cathodic overpotential and internal resistance of the cell exhibited almost the opposite dependence on the amount of doped Sr. Consequently, the power density of the cell was a maximum when Sm0.5Sr0.5CoO3 was used as the cathode. For this cell, the maximum power density was as high as 0.58 W/cm2 at 1073 K, even though a 0.5 mm thick electrolyte was used. This study revealed that a LaGaO3-based oxide for electrolyte and a SmCoO3-based oxide for the cathode are promising components for SOFCs operating at intermediate temperature..
507. Tatsumi Ishihara, Masakazu Higuchi, Toshiaki Takagi, Masami Ito, Hiroyasu Nishiguchi, Yusaku Takita, Preparation of CuO thin films on porous BaTiO3 by self-assembled multibilayer film formation and application as a CO2 sensor, Journal of Materials Chemistry, 10.1039/a801595c, 8, 9, 2037-2042, 1998.01, Preparation of CuO thin films by decomposition of self-assembled multibilayer films as a molecular template was investigated. Furthermore, the CO2 sensing property of the resultant CuO thin films on a porous BaTiO3 was investigated as a capacitive type sensor. Self-assembled bilayer films of a few 1000 layers thickness can be readily obtained by casting an aqueous suspension composed of dimethyldihexadecylammoniun bromide (DC1-16), Cu(CH3CO2)2, hexadecylethylenediamine and poly(vinyl alcohol). Divalent copper ions (Cu2+) which are associated with two hexadecylethylenediamine molecules were arranged in the hydrophobic layer of the multibilayer film. Rapid heating to the combustion temperature of DC1-16 was desirable for removing organic molecules in the multibilayer template. Thin films of CuO can be obtained by calcination at temperatures higher than 573 K. The resultant CuO thin films were porous and consisted of fine particles. The capacitance of CuO thin films prepared from self-assembled multibilayer films as a molecular template on the BaTiO3 porous substrate exhibited a high sensitivity to CO2, which is twice that of a conventional mixed oxide capacitor of CuO-BaTiO3. The capacitance of CuO thin films on BaTiO3 increases with increasing CO2 concentration in the range from 100 ppm to 50% at 873 K. Consequently, it is concluded that CuO thin films on BaTiO3 were appropriate capacitive type CO2 sensors..
508. Hiroyasu Nishiguchi, Akira Fukunaga, Yumi Miyashita, Tatsumi Ishihara, Yusaku Takita, Reduction of carbon dioxide to graphite carbon via methane by catalytic fixation with membrane reactor, Studies in Surface Science and Catalysis, 114, 147-152, 1998.01, Catalytic fixation of CO2 to graphite carbon in the temperature range above 500°C was investigated with membrane reactor. The process investigated in this study was consisted of two stage reaction, i. e., decomposition of CH4, into C and H2 and CO2 methanation with formed H2. Thus formed CH4 from CO2 was fed to first bed reactor to decompose to graphite carbon. It became evident that nickel supported on SiO2 was active for both reactions. Since the decomposition of CH4 was drastically increased with the application of membrane reactor system which considered of Pd alloy tube to CH4 decomposition. As a result, about 70% of CO2 can be reduced to graphite carbon at 500°C in this system. Furthermore, the high activity of catalyst was stably sustained over long period..
509. Hiroyasu Nishiguchi, Shuji Kimura, Tatsumi Ishihara, Yusaku Takita, Selective reduction of NOX with C3H6 over CU incorporated into silicoaluminophosphate (SAPO), Research on Chemical Intermediates, 10.1163/156856798X00447, 24, 4, 391-399, 1998.01, Cu ion-exchanged SAPO-34 which is a highly active catalyst for selective reduction of NO with C3H6, was synthesized and the Cu ion was characterized in the SAPO-34 by ESR, XPS, IR, and XAFS. ESR study indicated that two kinds of Cu(II) with different environments exist in SAPO-34. The Cu(II) species disappeared immediately by C3H6 treatment and recovered by oxygen treatment. XAFS study indicated that most of the Cu(II) was reduced to Cu(I) under the presence of C3H6. These studies revealed that a selective NO reduction by C3H6 over SAPO-34 should proceed by the redox reaction of a copper ion between Cu(I) and Cu(II)..
510. Hisao Sugihara, Tomoyuki Anan, Kentaro Adachi, Ayako Baba, Naoyoshi Egashira, Hiroyasu Nishiguchi, Tatsumi Ishihara, Yusaku Takita, Synthesis of disk-like calcium carbonate (Part 2)
Effect of various ethylenediamine compounds on the carbonation of basic calcium carbonate and mechanism of disk-like calcium carbonate synthesis, Journal of the Ceramic Society of Japan, 105, 10, 886-890, 1997.10, The addition of straight chain polyamines such as triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine and 1,4-diaminobutane in the course of carbonation of basic calcium carbonate promoted the formation of disk-like vaterite of 1-1.5 μm in diameter and 0.1-0.2 μm in thickness. On the other hand, cyclic polyamines such as piperazine, 1-(2-aminoethyl) piperazine and 1,4-diazabicyclo [2, 2, 2] octane, and branching polyamine such as 2,2-dimethylpropylene, promoted the formation of spindle-like calcite. Only polyamine in which N-N distance is 0.3 nm or its integral multiple, promoted formation of the disk-like calcium carbonate. Hexagonal of basic calcium carbonate once dissolved in aquarious media and the disk-like calcium carbonate formed..
511. T. Ishihara, H. Furutani, T. Yamada, Y. Takita, Oxide ion conductivity of double doped lanthanum gallate perovskite type oxide, Ionics, 10.1007/BF02375618, 3, 3-4, 209-213, 1997.05, Doping transition metal cation is known to enhance the electronic conduction of solid electrolytes, however, the ionic conduction can also be improved by those dopants. In this investigation, the oxide ion conductivity of LaGaO3 based oxide doped with transition metal cations such as Fe, Co, Ni, Mn, and Cu for the Ga site was studied. It was found that doping Co or Fe is effective for enhancing the oxide ion conductivity. The improved oxide ion conductivity may be induced by the improved mobility of oxide ion. Among examined transition metal cations, cobalt is the most adequate cation as a dopant for the Ga site of LSGM. Considering the conductivity and the transport number, the optimized composition is found to be La0.8Sr 0.2Ga0.8Mg0.115Co0.085O 3. In this work, application of Co2+ doped LSGM as the electrolyte of internally reformed fuel cells was also investigated. Improvement in oxide ion conductivity is effective for enhancing the power generation characteristics..
512. Tatsumi Ishihara, Masaru Kagawa, Fumiaki Hadama, Yusaku Takita, Copper ion-exchanged SAPO-34 as a thermostable catalyst for selective reduction of NO with C3H6, Journal of Catalysis, 10.1006/jcat.1997.1681, 169, 1, 93-102, 1997.01, Selective reduction of NO with C3H6 in the presence of oxygen was studied over Cu ion-exchanged SAPO-n (n=5, 11, 34), and Cu ion-exchanged Zeolites β, USY, and ZSM-5. All the Cu ion-exchanged catalysts exhibited high activity for NO reduction with C3H6 in a large excess of O2; however, the temperature for maximum NO conversion depended on the kind of molecular sieve. Although the maximum conversion of NO was attained at a slightly higher temperature in comparison with Cu-ZSM-5, Cu-SAPO-34 exhibited the highest activity for NO reduction among the catalysts studied under the conditions examined. Furthermore, high NO conversion was attained over a wide temperature range, from 623 to 873 K. SAPO-34 has high thermal stability. High activity for NO selective reduction on Cu-SAPO-34 was sustained for more than 60 h at 673 K in an atmosphere containing 15 vol% H2O. After thermal treatment at 1073 K in humidified atmosphere, the decrease in activity for NO reduction was also small. Redox behavior of Cu ions in SAPO-34 between monovalent and divalent states occurs during the selective reduction of NO, and the reaction seems to proceed via formation of adsorbed nitrate species followed by the formation of organic nitro compounds..
513. Tatsumi Ishihara, J. A. Kilner, M. Honda, Y. Takita, Oxygen surface exchange and diffusion in the new perovskite oxide ion conductor LaGaO3, Journal of the American Chemical Society, 10.1021/ja964128l, 119, 11, 2747-2748, 1997.01.
514. Yusaku Takita, Tatsumi Ishihara, Hiroyasu Nishiguchi, Hideaki Sumi, Palladium ion-exchanged SAPO-5 for a low temperature combustion of CH4, Studies in Surface Science and Catalysis, 105 B, 1647-1654, 1997.01, The oxidation activity of molecular sieves ion-exchanged by Pd were investigated as a catalyst for the low temperature combustion of CH4. Among the molecular sieves examined, SAPO-5 ion-exchanged by Pd exhibited the highest activity for CH4 combustion as well as the high thermal stability. Since the high dispersion of Pd particles was attained with ion-exchanged method, plateau in the temperature dependence of CH4 conversion was hardly appeared on Pd-HSAPO-5 catalysts in the high space velocity of CH4. Furthermore, the high activity of Pd-HSAPO-5 was sustained after the precalcination up to 1000°C. Consequently, Pd-HSAPO-5 is a promising combustion catalyst in low temperature range..
515. Tatsumi Ishihara, Junji Matsuo, Masami Ito, Hiroyasu Nishiguchi, Yusaku Takita, Porous H-ZSM-5 Zeolite Tube as a Novel Application of Catalyst for the Synthesis of Ethanol by Hydration of Ethylene, Industrial and Engineering Chemistry Research, 10.1021/ie9702338, 36, 10, 4427-4429, 1997.01, Gas-phase hydration of ethylene over a porous H-ZSM-5 tube was investigated. Yield of C2H5-OH is drastically increased by the porous H-ZSM-5 tube as a catalytic filter which has a function of catalyst and separator. The combination of the porous H-ZSM-5 tube with the powder H-ZSM-5 catalysts is effective for the synthesis of ethanol at high yield..
516. Tatsumi Ishihara, Masakazu Higuchi, Haruyoshi Furutani, Tomokatsu Fukushima, Hiroyasu Nishiguchi, Yusaku Takita, Potentiometric oxygen sensor operable in low temperature by applying LaGaO3-based oxide for electrolyte, Journal of the Electrochemical Society, 10.1149/1.1837632, 144, 5, 1997.01, A perovskite-type oxide of LaGaO3 doped with Sr and Mg exhibits a high oxide ion conductivity over a wide range of oxygen partial pressures. In this study, the application of LaGaO3-based oxide as the electrolyte of a potentiometric oxygen sensor was investigated. It became clear that silver is the most effective electrode for decreasing the operating temperature. Although a temperature higher than 800 K is required when a conventional Y2O3-stabilized ZrO2 electrolyte is used, an operating temperature as low as 600 K is adequate when La1-xSrxGa0.8Mg0.2O3 at X = 0.1 and 0.2 is used. The open-circuit potential was slightly smaller than that estimated with the Nernst equation. There was agreement with the Nernst equation down to 673 K when Nd-doped LaGaO3-based oxide was used. Moreover, 90% of the response was attained within 15 s at 673 K for the sensor with Nd-doped LaGaO3-based oxide..
517. Yusaku Takita, Gong Liang Li, Rie Matsuzaki, Hironori Wakamatsu, Hiroyasu Nishiguchi, Yoshihiko Moro-Oka, Tatsumi Ishihara, Stable and active AlPO4 catalyst for decomposition of CCl2F2, Chemistry Letters, 10.1246/cl.1997.13, 1, 13-14, 1997.01, CCl2F2 was decomposed to CO2 at 350-450 °C in the presence of water vapor and O2 over AlPO4 calcined at 1000 °C. CCl2F2 conversion slightly decreased at initial 50 h and then took a steady value. AlPO4 was not fluorinated during 1000 h reaction at 400 °C..
518. Tatsumi Ishihara, Masaru Kagawa, Fumiaki Hadama, Hiroyasu Nishiguchi, Masami Ito, Yusaku Takita, Thermostable Molecular Sieves, Silicoaluminophosphate (SAPO)-34, for the Removal of NOX with C3H6 in the Coexistence of O2, H2O, and SO2, Industrial and Engineering Chemistry Research, 10.1021/ie960389s, 36, 1, 17-22, 1997.01, Selective reduction of NO with C3H6 under an oxidizing atmosphere was studied over various Cu ion-exchanged molecular sieves. All examined Cu ion-exchanged catalysts are active for NO reduction with C3H6 in a large excess of O2; however, the temperature at the maximum NO conversion depends on the kind of molecular sieves. In particular, it was found that Cu-SAPO-34 is sometimes more active than Cu-ZSM-5. Thermal stability of SAPO-34 was extremely high, and consequently, decrease in the activity to NO selective reduction on Cu-SAPO-34 was negligible over 60 h at 673 K in an atmosphere containing 15 vol % H2O. After thermal treatment at 1073 K in a humidified atmosphere, decrease in the activity to NO reduction was also small. Although the activity of Cu-SAPO-34 to NO reduction was decreased slightly with the coexistence of SO2, it is expected that the activity of Cu-SAPO-34 is sustained over a long period..
519. Tatsumi Ishihara, Hiroki Fujita, Shinobu Sato, Tomokatsu Fukushima, Hiroyasu Nishiguchi, Yusaku Takita, Capacitive type NO sensor of CoO-In2O3 distinguishable from NO2, Denki Kagaku, 64, 12, 1321-1322, 1996.12.
520. Tatsumi Ishihara, Hiroki Fujita, Shinobu Sato, Tomokatsu Fukushima, Hiroyasu Nishiguchi, Yusaku Takita, Capacitive type NO sensor of CoO-In2O3 distinguishable from NO2, Electrochemistry, 64, 12, 1321-1322, 1996.12.
521. Tatsumi Ishihara, Hiroaki Mlnami, Hideaki Matsuda, Hiroyasu Nishiguchi, Yusaku Takita, Intermediate temperature solid oxide fuel cells with LaGaO3 based perovskite type electrolyte, Electrochemistry, 64, 6, 642-648, 1996.12, The electrical power generation characteristics of SOFCs where LaGaO3-based perovskite type oxide is applied as the electrolyte, were studied for the decreased temperature solid oxide fuel cells. The power generation characteristics of cells were strongly affected by the electrode, both anode and cathode. The maximum power density of cells increased in the following order, pt < La0.75Sr0.25CrO3 < (La0.6Sr0.4)0.9MnO3 < La0.6Sr0.4FeO3 < La0.6Sr0.4CoO3 for the cathode, and Ru < Pt < Co < Ni for the anode. Rare earth cations in the Ln-site of Co-based perovskite oxides cathode also have a great effect on the power generation characteristics. In particular, a high power density could be attained in the temperature range from 973 K to 1273 K by using a doped SmCoO3 for the cathode. The maximum power density of the SOFC, which consisted of Ni anode and Sm0.6Sr0.4CoO3 cathode attained the values as high as 0.44 and 0.14 W/cm2 at 1073 and 973 K, respectively..
522. Gong Liang Li, Tatsumi Ishihara, Moro Oka Yoshihiko, Takita Yusaku, Catalytic decomposition of HCFC22 (CHClF2), Applied Catalysis B: Environmental, 10.1016/0926-3373(96)90084-3, 9, 1-4, 239-249, 1996.09, The catalytic decomposition of CHClF2 was studied over various acidic metal oxides in a fixed-bed reactor. The Cr2O3-ZrO2 exhibited the highest activity. The presence of water vapor in the reaction system suppresses the transformation of oxides to fluorides, progresses the formation of CO2, and it improves the catalysts life..
523. Tatsumi Ishihara, Hideaki Matsuda, Mohamad Azmi Bin Bustam, Yusaku Takita, Oxide ion conductivity in doped Ga based perovskite type oxide, Solid State Ionics, 10.1016/0167-2738(96)00122-1, 86-88, PART 1, 197-201, 1996.07, Oxide ion conductivity of Ga based perovskite type oxides, LnGaO3 (Ln = Nd, La) and its related oxide, A3Ga2O6 (A = Ba and St) was investigated. Oxide ion transference number is almost 1.0 on Sr3Ga2O6 or Ba3Ga2O6. However, electrical conductivity of these A3Ga2O6 system oxides was lower than log (σ/S cm-1) = - 3 due to the low solubility of the aliovalent cations. On the other hand, doped perovskite type oxide of NdGaO3 and LaGaO3 exhibited a high electrical conductivity and the transference number of oxide ion was higher than 0.9 in the oxygen partial pressure range from PO2 = 1 to 10-21 atm. In particular, Ca and Mg doped NdGaO3 exhibited a high oxide ion conductivity in similar with LaGaO3 based oxide..
524. Yoshiko Hiei, Tatsumi Ishihara, Yusaku Takita, Partial oxidation of methane for internally reformed solid oxide fuel cell, Solid State Ionics, 10.1016/0167-2738(96)00299-8, 86-88, PART 2, 1267-1272, 1996.07, Internally reformed solid oxide fuel cells (SOFC) where partial oxidation of methane was used as the reforming reaction were investigated. The electrical power generated as well as the activity for the partial oxidation of methane are strongly dependent on the oxide ion conductivity of the electrolyte used. Among the oxide ion conductors examined, perovskite oxide of LaGaO3 doped with Sr and Mg gives the highest electrical power, and a gaseous mixture of CO and H2 at the molar ratio of 2 was obtained. When La0.9Sr0.1Ga0.8Mg0.2O3, Ni, and La0.6Sr0.4CoO3 were used as electrolyte, anode, and cathode, respectively, and the gaseous mixture of CH4/O2 = 4 was fed, the electrical power density and yield of synthesis gas consisting of CO and H2 attained was 336 mW cm-2 and 70%, respectively. The electrical power as well as the CH4 conversion was stably sustained over a 30 h examination..
525. Tatsumi Ishihara, Keiji Sato, Yusaku Takita, Electrophoretic deposition of Y2O3-stabilized ZrO2 electrolyte films in solid oxide fuel cells, Journal of the American Ceramic Society, 10.1111/j.1151-2916.1996.tb08525.x, 79, 4, 913-919, 1996.01, An electrophoretic deposition (EPD) method was applied for the preparation of yttria-stabilized zirconia (YSZ) films for solid oxide fuel cell (SOFC) applications. Dense YSZ films with uniform thickness can be readily prepared with the EPD method by using acetylacetone or acetone as a solvent. The open-circuit voltages of SOFC, for which the YSZ films were prepared by the EPD method, increased with increasing repetitions of deposition and sintering. It was found that the open-circuit voltage exceeded 1.0 V after five repetitions. When the planar SOFC was fabricated using La0.6Sr0.4MnO3 as a cathode, and electroless plating Pt as an anode, the open-circuit voltage and the maximum power density attained were 1.03 V and 1.84 W·cm-2, respectively. Consequently, it became evident that the electrophoretic deposition was a suitable processing route for the formation of gas-tight YSZ films with thickness less than 10 μm..
526. Gong Liang Li, Tatsumi Ishihara, Hiroyasu Nishiguchi, Yoshihiko Moro-Oka, Yusaku Takita, Novel catalysts effective for dehydrofluorination of CF3CH3 (HFC143a) into CF2CH2, Chemistry Letters, 10.1246/cl.1996.507, 7, 507-508, 1996.01, The catalytic dchydrofluorination of CF3CH3 into CF2CH2 was studied over various metal phosphates in a fixed-bed reactor. The Mg2P2O7 catalyst exhibited moderate activity, higher selectivity and greater stability. The active sites for CF2CH2 formation are weak acid sites of the catalysts..
527. Tatsumi Ishihara, Shinobu Sato, Yusaku Takita, Sensitive detection of nitrogen oxides based upon capacitance changes in binary oxide mixture, Sensors and Actuators, B: Chemical, 10.1016/0925-4005(95)01744-G, 30, 1, 43-45, 1996.01, The capacitance of mixed oxides consisting of oxides with different semiconducting properties decreases upon exposure to NO. In particular, the mixed oxide NiO-WO3 exhibits an extremely large capacitance decrease upon exposure to 100 ppm NO, but a period longer than 30 min is required to recover the original capacitance level after changing to air without NO. On the other hand, the mixed oxide WO3-ZnO exhibits a large capacitance decrease upon exposure to NO and its capacitance decreases with increases in the NO concentration up to 300 ppm. Therefore, the concentration of nitrogen oxide can be analysed by the capacitance of these mixed oxides..
528. Tatsumi Ishihara, Shinobu Sato, Tomokatsu Fukushima, Yusaku Takita, Capacitive gas sensor of mixed oxide CoO-In2O3 to selectively detect nitrogen monoxide, Journal of the Electrochemical Society, 10.1149/1.1836923, 143, 6, 1908-1914, 1996.01, Selective detection of nitric oxide, NO, based on the capacitance change of a mixed-oxide capacitor was investigated. Since the capacitance of an oxide mixture consisting of two kinds of semiconductive oxides depends on the NO concentration, the NO concentration can be estimated from the capacitance of these mixed-oxide capacitors. In particular, the capacitance of the physical mixture of CoO and In2O3 was highly sensitive and selective to NO. Although the sensitivity to NO was decreased, the period for recovery was extremely shortened by increasing the operating temperature. In considering the sensitivity and response characteristics, the optimum operating temperature of CoO-In2O3 seems to exist around 500 K. Whereas the sensitivity to NO diluted with N2 was higher than that in air, the sensitivity to NO was almost independent of the oxygen partial pressure over a wide range. Furthermore, the capacitance of CoO-In2O3 increased with increasing concentration of NO in the range from 1 to 1000 ppm. The sensitivity of CoO-In2O3 to CO2, CO, and SO2 was far smaller than that to NO. Consequently, a mixed oxide of CoO-In2O3 is one of the promising materials for the detection of NO in exhaust gases..
529. Tatsumi Ishihara, Hiroaki Minami, Hideaki Matsuda, Hiroyasu Nishiguchi, Yusaku Takita, Decreased operating temperature of solid oxide fuel cells (SOFCs) by the application of LaGaO3-based oxide as electrolyte, Chemical Communications, 10.1039/cc9960000929, 8, 929-930, 1996.01, Application of the new oxide ion conductor of composition La0.9Sr0.1Ga0.8Mg0.2O3 as electrolyte in solid oxide fuel cells is effective in enabling a decrease in the operating temperature..
530. Tatsumi Ishihara, Hiroaki Minami, Hideaki Matsuda, Hiroyasu Nishiguchi, Yusaku Takita, Intermediate temperature solid oxide fuel cells with LaGaO3 based perovskite type electrolyte, Denki Kagaku, 64, 6, 642-648, 1996.01, The electrical power generation characteristics of SOFCs where LaGaO3-based perovskite type oxide is applied as the electrolyte, were studied for the decreased temperature solid oxide fuel cells. The power generation characteristics of cells were strongly affected by the electrode, both anode and cathode. The maximum power density of cells increased in the following order, Pt < La0.75Sr0.25CrO3 < (La0.6Sr0.4)0.9MnO3 < La0.6Sr0.4FeO3 < La0.6Sr0.4CoO3 for the cathode, and Ru < Pt < Co < Ni for the anode. Rare earth cations in the Ln-site of Co-based perovskite oxides cathode also have a great effect on the power generation characteristics. In particular, a high power density could be attained in the temperature range from 973 K to 1273 K by using a doped SmCoO3 for the cathode. The maximum power density of the SOFC, which consisted of Ni anode and Sm0.6Sr0.4CoO3 cathode attained the values as high as 0.44 and 0.14 W/cm2 at 1073 and 973 K, respectively..
531. Tatsumi Ishihara, Hideaki Matsuda, Yusaku Takita, Effects of rare earth cations doped for La site on the oxide ionic conductivity of LaGaO3-based perovskite type oxide, Solid State Ionics, 10.1016/0167-2738(95)00054-A, 79, C, 147-151, 1995.07, For the suppression of hole conduction in the high oxygen partial pressure range, effects of the addition of small amount of rare earth cations were investigated in this study with La0.8Sr0.2Ga0.8Mg0.2O3 - δ. It was found that the addition of small amount of rare earth cations for La site in LaGaO3 was effective for the suppression of hole conduction under high oxygen partial pressure, albeit the electrical conductivity decreased slightly. In particular, perovskite oxide of (La0.9Nd0.1)0.8Sr0.2Ga0.8Mg0.2O3 - δ exhibits almost pure oxide ionic conduction over the oxygen partial pressure from 1 to 10-21 atm, and the electrical conductivity attains the value of log (σ/S cm-1) = -0.5 at 1223 K..
532. Tatsumi Ishihara, Kazuhiro Kometani, Yuichiro Nishi, Yusaku Takita, Improved sensitivity of CuOBaTiO3 capacitive-type CO2 sensor by additives, Sensors and Actuators: B. Chemical, 10.1016/0925-4005(94)01539-T, 28, 1, 49-54, 1995.07, The sensitivity of a CuOBaTiO3 capacitive-type CO2 sensor has been enhanced by the addition of metal or metal oxides except for Au, Fe2O3, CeO2 and Rh, whereas the operating temperature shifts slightly to a higher temperature and the response time is prolonged. In particular, the change in capacitance caused by CO2 is markedly enlarged by the addition of ZnO, Bi2O3, SrO and Ag. Among these additives, silver is the most suitable from the viewpoints of sensitivity and operating temperature. The CuOBaTiO3 plus Ag sensor can detect CO2 over four orders of magnitude of concentration from capacitance measurement. Furthermore, the positive effects of Ag addition on sensitivity are obtained only for CO2 and CO. Therefore, CuOBaTiO3 sensors exhibit extremely high selectivity to CO2 detection in spite of the chemical stability of CO2. The improved sensitivity due to Ag addition is reproducible and exhibits almost constant sensitivity to 5000 ppm CO2 over a period of 30 days..
533. Tatsumi Ishihara, Yoshiko Hiei, Yusaku Takita, Oxidative reforming of methane using solid oxide fuel cell with LaGaO3-based electrolyte, Solid State Ionics, 10.1016/0167-2738(95)00090-S, 79, C, 371-375, 1995.07, Simultaneous production of thermal energy, electric power, and gaseous mixture of CO and H2, suitable for the methanol synthesis was possible by the application of a solid oxide fuel cell to the catalytic reactor. In particular, large electric power as well as high yields of CO and H2 were obtained upon the fuel cell reactor where La0.9Sr0.8Ga0.8Mg0.2O3 perovskite-type oxide was used as solid electrolyte. The high electrical power density as well as the high yield of CO and H2 were stably sustained over the examined 30 h..
534. Tatsumi Ishihara, Shinobu Sato, Yusaku Takita, Capacitive-type sensors for the selective detection of nitrogen oxides, Sensors and Actuators: B. Chemical, 10.1016/0925-4005(95)85088-0, 25, 1-3, 392-395, 1995.04, Since the capacitance of an oxide mixture consiting of two kinds of semiconducting oxides depends on the NO concentration, these mixed-oxide capacitors can be applied for a capacitive type of NOx sensor. Among the examined oxides, NiO mixed with ZnO was the most promising in terms of the sensitivity and response characteristics. A temperature slightly higher than 300°C was desirable as the operating temperature of the NiO-ZnO element, and a linear relationship between capacitance and NOx concentration exists below 30 ppm. Furthermore, the capacitance of NiO-ZnO is highly selective to NOx. As a result, the binary oxide of NiO-ZnO has a great potential as a new type of NOx sensor based on a capacitance change..
535. Tatsumi Ishihara, Takanari Kudc, Hideaki Matsudc, Yusaku Takita, Doped PrMn03Perovskite Oxide as a New Cathode of Solid Oxide Fuel Cells for Low Temperature Operation, Journal of the Electrochemical Society, 10.1149/1.2048606, 142, 5, 1519-1524, 1995.04, Cathodic overpotentials of Ln0.6Sr0.4Mn03(Ln = La, Pr, Nd, Sm, Gd, Yb, and Y) were studied for a new cathode of solid oxide fuel cell (SOFC). Cathodic overpotentials as well as the electrical conductivity strongly depended on the rare earth cations used for the A sites of perovskite oxide. Strontium doped PrMnO3exhibited the highest electrical conductivity among the examined perovskite oxide containing Mn for B sites. Moreover, overpotentials of Sr-doped PrMnO3cathode maintained low values in spite of decreasing the operating temperature. Consequently, almost the same power density of SOFC with La0.6Sr0.4Mn03cathode can be obtained at about 100 K lower operating temperature by using Sr-doped PrMnO3as the cathode. The overpotentials and electrical conductivity decreased and increased with increasing the amount of Sr dopant in PrMnO3, respectively, and the lowest overpotential was attained at x = 0.4 in Pr1-xSrxMnO3. Comparing with La0.6Sr0.4MnO3oxide, the reactivity of Pr0.6Sr0.4MnO3with Y2O3-stabilized ZrO2is much less than that of La0.6Sr0.4MnO3 and furthermore, the matching of thermal expansion of Pr0.6Sr0.4MnO3with Y2O3-ZrO2was satisfactorily high. Therefore, perovskite oxide of Pr0.6Sr0.4MnO3has a great possibility of the cathode materials for decreasing the operating temperature of solid oxide fuel cells..
536. Yukako Mizuhara, Masao Noguchi, Tatsumi Ishihara, Yusaku Takita, Preparation of Silicon Nitride Whiskers from Diatomaceous Earth
I, Reaction Conditions, Journal of the American Ceramic Society, 10.1111/j.1151-2916.1995.tb08368.x, 78, 1, 109-113, 1995.01, Whiskers and powder of silicon nitride were prepared by the carbothermal reduction and nitridation of diatomaceous earth in the presence of flowing N2 and NH3. The optimum temperature for the formation of Si3N4 whiskers was 1350°C and the yield reached almost 20% after 24 h. The α‐Si3N4 content decreased with increasing nitridation temperature. Yields of the whiskers were dependent on NH3 concentration and the total gas feed rate. The maximum yield of inside whiskers was obtained for a 25 vol% NH3/N2 mixture, while the maximum quantity of outside whiskers was produced for 75 vol% NH3/N2. The sum of the yield of the inside and outside whiskers increased with decreasing total gas feed rate. However, no nitridation of SiO2 was observed at a feed gas rate below 0.18 mmol·min−1. The yield of the inside whiskers increased gradually with increasing reaction time up to 36 h, whereupon a constant value was attained. Although the amount of outside whiskers produced was relatively small, the quantity seemed to increase until 60 h..
537. Tatsumi Ishihara, Hideaki Matsuda, Yusaku Takita, Oxide Ion Conductivity in Doped NdAlO3 Perovskite-Type Oxides, Journal of the Electrochemical Society, 10.1149/1.2059351, 141, 12, 3444-3449, 1994.12, Oxide ion conductivity in doped NdA103Perovskite-type oxides was investigated. Among the alkaline earth cations, the addition of Ca for Nd site is effective for increasing the oxide ion conductivity of NdAlO3. Oxide ion conductivity increased anomalously with increases in the amount of Ca, and attained the maximum at x = 0.1 in Nd1-xCaxAlO3, since the limit of the solid solution of Ca into the Nd site seems to be around x = 0.1. The addition of the cations for the Al site of Nd0.9Ca0.1AlO3 was also effective for increasing the oxide ion conductivity, and it was found that the substitution of Ga on A1 sites is effective for enhancing the oxide ion conductivity of Nd0.9CaO.1AlO3. The oxide ion conductivity increased with increasing the Ga content and the highest oxide ion conductivity was attained at x = 0.5 in Nd0.9Ca0.1Al1-xGaxO3. Since the increased oxygen ion conductivity by doping Ga suppressed the p-type semiconduction in high oxygen partial pressure range, electrical conductivity was almost independent of the oxygen partial pressure. The theoretical electromotive forces were obtained from the galvanic cell measurement where Nd0.9Ca0.1Al0.5Ga0.5O3 was used as the electrolyte. Furthermore, the fuel cell where Nd0.9Ca0.1Al0.5Ga0.5O3, Ni, and La0.6Sr0.4MnO3 were used as electrolyte, anode, and cathode, respectively, exhibited the short-circuit current density higher than 400 mA cm-2 at 1273 K, when humidified H2 and O2 were used as fuels and oxidizing agent, respectively. These results suggest that the perovskite-type oxide, Nd0.9Ca0.1Al0.5Ga0.5O3, exhibits almost a pure oxide ion conductivity with high electrical conductivity over a wide range of oxygen partial pressures and temperatures..
538. Yukako Mizuhara, Masao Noguchi, Tatsumi Ishihara, Yusaku Takita, Effects of various reducing agents on the synthesis of Si3N4 whiskers from diatomaceous earth, Journal of the Ceramic Society of Japan. International ed., 102, 7, 640-645, 1994.07, Diatomaceous earth were subjected to carbothermal reduction and nitridation in a flow of nitrogen containing various reducing agents; NH3, H2, CO, and CH4. It was found that a carbon plate or mathane are capable of reducing SiO2, but neither H2 nor CO. The effect of addition of powdered carbon to diatomaceous earth was also studied. Results were obtained in terms of the yields both outside and inside the whiskers..
539. Yukako Mizuhara, Hiroshi Ono, Masao Noguchi, Tatsumi Ishihara, Yusaku Takita, Effects of metal oxides on the synthesis of Si3N4 whiskers from diatomaceous earth, Journal of the Ceramic Society of Japan. International ed., 102, 6, 588-594, 1994.06, To determine the effects of metal oxides on the whisker shapes and production yield as well as the role of these oxides in the starting material in trace quantities, diatomaceous earth and high-purity SiO2 were subjected to reduction and nitridation in a flowing mixture of nitrogen and ammonia. The results showed that the growth of outside whiskers was brought about by the vapor-liquid-solid (VLS) mechanism and that Fe is necessary for the growth of the outside whiskers. It was also assumed that manganese and iron oxides present in the diatomaceous earth were reduced to metallic Mn and Fe..
540. Tatsumi Ishihara, Hideaki Matsuda, Yusaku Takita, Doped LaGaO3 Perovskite Type Oxide as a New Oxide Ionic Conductor, Journal of the American Chemical Society, 10.1021/ja00088a016, 116, 9, 3801-3803, 1994.05, Doped LaGaO3 exhibits high oxide ionic conductivity. Doping of Sr for the La site and Mg for the Ga site is the most effective method for enhancing the oxide ionic conductivity of LaGaO3. The oxide ionic conductivity of La0.9Sr0.1Ga0.8Mg0.2O3 was higher than that of Sc-doped ZrO2 and slightly lower than that of Bi2O3 oxide. Furthermore, electronic or hole conduction was negligibly small in the oxygen partial pressure region from 1 to 10-20 atm..
541. Yukako Mizuhara, Hiroshi Ono, Tatsumi Ishihara, Yusaku Takita, Preparation of Si3N4 whiskers from various natural resources, Journal of the Ceramic Society of Japan. International ed., 102, 5, 489-494, 1994.05, Silicon nitride whiskers have been prepared by reduction and nitridation of natural resources, produced in Oita prefecture, such as Asono diatomaceous earth, Beppu terra abla, Youra quartzite and molding sand, at 1370 °C in an NH3-N2 stream on a carbon plate. Two types of Si3N4 whiskers, short needlelike whisker (inside whisker) and woollike whisker (outside whisker) were obtained from the inexpensive raw materials. The shape of these whiskers, however; varied with the intrinsic composition of the starting materials. The outside whiskers obtained from the molding sand were almost all composed of Si3N4 with a few whiskers composed mainly of Al, and which looked like abacus or connected hexagonal beads. The outside whiskers obtained from the four kinds of raw materials had droplets on one of their ends, indicating that the outside whiskers grow by the VLS mechanism. The droplets produced from diatomaceous earth and quartzite were mainly composed of Fe and Si. On the other hand, those from tetra abla were composed of Fe, Si and a small amount of Ti. In the case of the molding sand, two types of droplets, one composed of Fe and Si and the other composed of Cr, Fe and Si, were observed. These metals, which composed the droplets, were derived from metal oxides in the raw materials. The metal elements are thought to have migrated from the starting material to the outside whisker in a vapor phase..
542. Tatsumi Ishihara, Masaru kagawa, Fumiaki Hadama, Yusaku Takita, Copper Ion Exchanged Silicoaluminophosphate (SAPO) as a Thermostable Catalyst for Selective Reduction of NOX with Hydrocarbons, Studies in Surface Science and Catalysis, 10.1016/S0167-2991(08)63692-7, 84, C, 1493-1500, 1994.01, Selective reduction of NO with C3H6 under oxidizing atmosphere was studied over Cu-ion exchanged SAPO-n (n=5, 11, 34), β, USY, and ZSM-5. All examined Cu-ion exchanged catalyst exhibited the high activity for NO reduction with C3H6 and a large excess of 02, however, the temperature at the maximum NO conversion depends on the kind of molecular sieves. Although the maximum conversion of NO attained at a slightly higher temperature comparing with Cu-ZSM-5, Cu-SAPO-34 exhibited the highest activity for NO reduction among the examined catalysts. Furthermore, the high NO conversion was attained over a wide temperature range from 250 to 600° C. Thermal stability of SAPO-34 was extremely high and consequently, high activity to NO selective reduction on Cu-SAPO-34 was hardly decreased over 60 h at 400° C in an atmosphere containing 15 vol% H2O, and after thermal treatment at 800° C in humidified atmosphere, decreases in the activity for NO reduction was also small..
543. Tatsumi Ishiham, Takanari Kudo, Hideaki Matsuda, Yusaku Takita, Doped Perovskite Oxide, PrMnO3, as a New Cathode for Solid‐Oxide Fuel Cells that Decreases the Operating Temperature, Journal of the American Ceramic Society, 10.1111/j.1151-2916.1994.tb09779.x, 77, 6, 1682-1684, 1994.01, Cathodic overpotentials of Ln0.6Sr0.4MnO3 (Ln is La, Pr, Nd, Sm, Gd, Yb, and Y) were studied for a new cathode for solid‐oxide fuel cells (SOFCs) with low overpotentials in a relatively‐low‐temperature region. Cathodic overpotentials strongly depended on the rare‐earth cations in the A sites of the perovskite oxide. In particular, overpotentials of a Sr‐doped PrMnO3 cathode maintained low values despite decreased operating temperature. Consequently, almost the same power density of a SOFC with Ln0.6Sr0.4MnO3 cathode was obtained at about 100 K lower operating temperature by using Sr‐doped PrMnO3 as the cathode..
544. Tatsumi Ishihara, Hideaki Matsuda, Yukako Mizuhara, Yusaku Takita, Improved oxygen ion conductivity of NdAlO3 perovskite-type oxide by doping with Ga, Solid State Ionics, 10.1016/0167-2738(94)90316-6, 70-71, PART 1, 234-238, 1994.01, Effects of Ga addition to NdAlO3 on the oxygen ion conductivity were studied. Substitution of Ga to Al sites is effective for enhancing the oxygen ion conductivity of Nd0.9Ca0.1AlO3 and the highest oxygen ion conduction was obtained at x=0.5 in Nd0.9Ca0.1Al1-xGaxO3. Since the increased oxygen ion conduction by doping Ga suppressed the p-type semic onduction at high oxygen partial pressure, electrical conductivity was almost independent of the oxygen partial pressure in a range from PO2=1 to 10-20 atm. The oxygen ion conductivity of Nd0.9Ca0.1Al0.1Ga0.5O3 at 1223 K is as high as log (σ/S cm-)=-1.4, and furthermore, the oxide ion transference number is estimated to be almost 1.0 over a wide range of oxygen partial pressure and temperature..
545. Y. Takita, K. Kurosaki, T. Ito, Y. Mizuhara, Tatsumi Ishihara, Role of Acidic Sites on Metal Phosphates in the Catalytic Oxidation of iso-Butane, Studies in Surface Science and Catalysis, 10.1016/S0167-2991(08)61855-8, 90, C, 441-446, 1994.01, Catalysis by lanthanide phosphates (LnPs) were studied. Only LaPO4 and CePO4 are effective catalysts in various LnPs for oxidative dehydrogenation of iso-butane. Using a iso-butane rich reactant gas mixture, the selectivity of iso-butene showed 79-86% at 450-550°C. LnPs have no adsorbed oxygen species and the surface lattice oxygen reacted with hydrogen at >200°C. The activity of the lattice oxygen not affected the catalytic activity. A linear relationship has observed between the acid amount and the catalytic activity of the catalysts. This suggests that acidic sites of intermediate strength play a key role in the oxidative dehydrogenation of iso-butane..
546. Yusaku Takita, Katsuyoshi Tanaka, Shiro Ichimaru, Yukako Mizihara, Yumi Abe, Tatsumi Ishihara, Incorporation of promoter elements into the crystal lattice of (VO)2P2O7 and its promotion effects on the oxidation of n-butane to maleic anhydride, Applied Catalysis A, General, 10.1016/0926-860X(93)85058-W, 103, 2, 281-290, 1993.09, A new preparation method to introduce promoter ions into the (VO2)P2O7crystal lattice was developed. A precipitate was obtained by the addition of a small amount of water to a blue isobutanol refluxing solution which contained reduced and dissolved V2O5 and the acetylacetonate of a promoter element. The catalyst which was prepared by the calcination of this precipitate had the same composition as that of the starting solution. Observation of the catalyst using energy-dispersive X-ray and wavelength-dispersive X-ray showed no evidence of localization of the added promoter element. The ESCA (electron spectroscopy for chemical analysis) depth profile of the component elements suggested a homogeneity between the surface and the bulk of the catalyst. There is a linear relationship between the activity of the catalysts for MA formation and the position of the VO IR absorption bands of the catalysts containing promoter elements. The active sites of the catalysts and the activity of the surface VO are discussed..
547. Tatsumi Ishihara, Kazuhiro Kometani, Yukako Mizuhara, Yusaku Takita, Capacitive-type gas sensor for the selective detection of carbon dioxide, Sensors and Actuators: B. Chemical, 10.1016/0925-4005(93)85429-E, 13, 1-3, 470-472, 1993.05, The capacitances of CuO mixed with BaSnO3, CaTiO3, and ZnO are dependent on the CO2 concentration, similarly to that of CuO-BaTiO3. In particular, the mixed oxide CuO-SrTiO3 is more sensitive to CO2 than CuO-BaTiO3, and the mixed-oxide capacitor CuO-BaSnO3 is promising for sensing CO2 over a wide range of concentrations. Moreover, addition of Ag to CuO-BaTiO3 mixed oxide is effective for enhancing the sensitivity to CO2. The sensitivity (CCO2/Cair) to 2% CO2 of Ag-added CuO-BaTiO3, which has been calcined at 700 °C followed by operation for 60 h, is as high as 70..
548. Yukako Mizuhara, Masao Noguchi, Tatsumi Ishihara, Yusaku Takita, Toru Shiomitsu, Hiromichi Arai, Microstructure of Si3N4 whisker prepared from diatomaceous earth, Journal of the European Ceramic Society, 10.1016/0955-2219(93)90130-J, 12, 2, 111-116, 1993.01, Silicon nitride whiskers were prepared by carbothermal reduction and nitridation of diatomaceous earth at temperature of 1350°C under the presence of nitrogen and ammonia. Scanning and transmission electron microscopy (SEM), electron probe micro-analysis (TEM) and X-ray diffraction were used to characterize the microstructure. SEM studies indicated that the whiskers were quite straight and hexagonal in cross-section. The whiskers were found to be highly crystalline, as determined by TEM analysis..
549. Naoji Kubota, Yasuo Kikuchi, Yukako Mizuhara, Tatsumi Ishihara, Yusaku Takita, Solid‐phase modification of chitosan hydrogel membranes and permeability properties of modified chitosan membranes, Journal of Applied Polymer Science, 10.1002/app.1993.070500921, 50, 9, 1665-1670, 1993.12, A novel preparation method for modified chitosan membranes was developed. Chitosan hydrogel membranes were prepared by immersing an aqueous acetic acid solution of chitosan in KOH solution and modified with 3,3′‐dithiodipropionic acid (DTPA), which has a functional group that causes the thiol ⟷ disulfide transition through a redox reaction. It was smoothly modified with DTPA even in a solid‐phase modification when carbodiimides were used as the condensing reagents. The chitosan membrane modified with DTPA was reduced with tri‐n‐butyl phosphine (MSH membrane) and then oxidized with iodine (MSS membrane). Permeabilities of KCl, sucrose, and urea through these modified chitosan membranes were investigated. The permeability of urea was quite high and followed by KCl and sucrose in that order. The permeabilities of KCl and sucrose through the MSS membrane showed a decrease compared to those through the MSH membrane. The thiol ⟷ disulfide transition was responsible for changes in the permeabilities of KCl and sucrose. The permeability of urea was almost the same for both membrane systems, i.e., permeation of urea was not affected by the thiol ⟷ disulfide transition, probably due to the break of hydrogen bonding in the membranes. © 1993 John Wiley & Sons, Inc..
550. Yusaku Takita, Takeshi Imamura, Yukako Mizuhara, Yumi Abe, Tatsumi Ishihara, Selective hydrogen cyanide synthesis from CFC12 (CCl2F2) and ammonia over metal catalysts supported on LaF3 and activated charcoal, Applied Catalysis B, Environmental, 10.1016/0926-3373(92)80034-W, 1, 2, 79-87, 1992.06, The applicability of supports such as LaF3, activated charcoal and Cr2O3 to the new reaction, CCl2F2 + 5 3NH3→HCN + 2HCl + 2HF + 1 3N2 was examined and it was found that TiO2 itself reacted with CFC12 to give carbon monoxide and carbon dioxide even at 673 K in addition to hydrogen cyanide formation. LaF3 did not react with CFC (chlorofluorocarbon) even at 823 K so that it could be considered suitable for use as a catalyst support. Au(1 wt.-%)/LaF3 and Pt(1 wt.-%)/LaF3 were effective for hydrogen cyanide formation and hydrogen cyanide selectivity reached 77-78% at 823 K. Activated charcoal was also suitable for use as a catalyst support and hydrogen cyanide was formed selectively (72-84%) over Rh(1 wt.-%)/AC and Pd(1 wt.-%)/AlF3/AC catalysts at 823 K..
551. Tatsumi Ishihara, Koichi Eguchi, Hiromichi Arai, Importance of surface hydrogen concentration in enhancing activity of CoNi alloy catalyst for CO hydrogenation, Journal of Molecular Catalysis, 10.1016/0304-5102(92)80050-Q, 72, 2, 253-261, 1992.03, The hydrogen-deuterium exchange reaction was employed for studying the reactivity of adsorbed hydrogen on CoNi alloy. The infrared spectra of adsorbed NO indicates that the support oxide electronically interacts with the CONi alloy. Desorption measurements suggest that the electron density of the alloy greatly influences the surface coverage of hydrogen and carbon monoxide. The CO hydrogenation rate of CoNi alloy in the presence of CO was shown to be related to the H2D2 exchange rate. The dissociative adsorption of hydrogen in the presence of CO is of primary importance in determining the CO hydrogenation rate of the CoNi alloy system, since the preadsorbed CO species strongly hinder the hydrogen adsorption. A high surface concentration of active hydrogen in the presence of CO leads to high catalytic activity for CO hydrogenation on CoNi alloy..
552. Tatsumi ishihara, Kazuhiro Kometani, Yukako Mizuhara, Yusaku Takita, Application of a Mixed Oxide Capacitor to the Selective Carbon Dioxide Sensor II. CO2 Sensing Characteristics of a Cuo-Based Oxide Capacitor, Journal of the Electrochemical Society, 10.1149/1.2068999, 139, 10, 2881-2885, 1992.01, Characteristics for CO2 sensing of a CuO-based oxide capacitor were studied. The capacitances of CuO mixed with BaSnO3 SrTiO3, CaTiO3, and ZnO are dependent on the CO2 concentration, similar to CuO-BaTiO2. In particular, the mixed oxide, CuO-SrTiO3, is more sensitive to CO2 than CuO-BaTiO3, but requires a rather long time to recover. On the other hand, the mixed oxide capacitor, CuO-BaSnO3, exhibits high CO2 sensitivity, and a monotonic and approximately logarithmic relationship exists between the sensitivity and the concentration of CO2 from 100 ppm to 50%. Furthermore, the capacitance of CuO-BaSnO3 increased rapidly within 30s after exposure to 2% CO2, and returned rapidly to the original level after reexposure to air. Therefore, the system, CuO-BaSnO3 is promising for sensing CO2 over a wide range of concentrations. From a complex impedance measurement, the equivalent circuit of the sensor element can be expressed by a series connection of three parallel resistors and capacitors which correspond to the intragrain region, grain interface between CuO and BaSnO3, and electrode interface. Since exposure of the element to 2% CO2 varied the capacitance of the grain interface, the grain interface between CuO and BaSnOa has an important role for CO2 detection..
553. Yusaku Takita, Hiroshi Yamada, Kouji Yoshida, Yukako Mizuhara, Tatsumi Ishihara, Dechlorohydrogenation of CFC 113 (CCI2FCCIF2) over Metal Catalysts Supported on Fluorides, NIPPON KAGAKU KAISHI, 10.1246/nikkashi.1992.9, 1992, 1, 9-16, 1992.01, Hydrodechlorination, dechlorohydrogenation, and isomerization of CFC 113 took place over Ni, Pd, Pt, Au catalysts supported on fluorides at 200—550 °C in the presence of hydrogen. Over Ni/CeF3j Ni/LaF3, and Ni/CaF2 catalysts, C2C1F3(I) and CH4 were formed selectively at <350°C and at >450 °C, respectively. Compound (I) was a major product at 250—550 °C over Ni/PbF2 and Ni/MnF2 catalysts. CFC 113 was converted at > 150-200 °C over Pd/CeF3 and Pd/LaF3 and the conversion increased with increasing temperature. The conversion gave a maximum of 85% at 300 °C and a minimum of 10∼15% at 450∼500 °C and then increased again with increasing temperature. CF3CC1H2(II) and CF3CCl2H(III) were formed at <350 °C and the selectivity of (F) increased to 90% at 550 °C from 50% at 150 °C over Pd/CeF3. Compounds (II) + (F), C2F3H, and (I) were formed successively with increasing temperature over Pd/LaF3. Pd/MnF2 was less active for the reaction. Compounds (II) + (III) and CFHCFH(V) were major products at <250°C and at 300—500 °C, respectively, over Pt/CeF3. (IE) and (V) were produced slectively at <250 °C and 250-500 °C over Pt/LaF3} respectively. Activity of Pt/MnF2 was relatively low, and the high selectivity, 80—100%, was maintained at all reaction temperatures. Compound(I) was a major product at >350°C over Au/MnF2 and Au/CeF3. No changes in acitivity and selectivity were observed after 55 h at 300 °C over Ni/CaF2. β-PbF2 changed into PbCl2 during the reaction, however, the other fluorides reacted with neither CFC 113 nor supported metals. Specific surface areas of Pd/CeF3 and Au/CeF3 increased after the reaction. Dispersion of Pd increased during the reaction over fluoride supports..
554. Tatsumi Ishihara, Nobuhiko Horiuchi, Takanori Inoue, Koichi Eguchi, Yusaku Takita, Hiromichi Arai, Effect of alloying on CO hydrogenation activity over SiO2-supported CoNi alloy catalysts, Journal of Catalysis, 10.1016/0021-9517(92)90122-X, 136, 1, 232-241, 1992.01, Alloying Co with Ni is effective for enhancing the activity for CO hydrogenation as well as the selectivity to gasoline. Infrared spectra of adsorbed NO and XPS spectra for the 3p 3 2 Orbital of Co and Ni suggest that Co in the alloy interacts electronically with Ni in the outer shell orbital, resulting in the creation of adsorption sites with a new electron density. As a result, alloying Co with Ni strengthens the hydrogen adsorption. Thus alloying Co with Ni allows hydrogen to compete more effectively for adsorption sites in the co-adsorption of CO and H2. Since the rate of H2D2 exchange on CO preadsorbed CoNi alloy shows a good correlation with the CO hydrogenation activity, the reactivity of adsorbed hydrogen in the presence of CO plays a decisive role in determining the activity for CO hydrogenation in this alloy system..
555. Tatsumi Ishihara, Kazuaki Harada, Koichi Eguchi, Hiromichi Arai, Electronic interaction between supports and ruthenium catalysts for the hydrogenation of carbon monoxide, Journal of Catalysis, 10.1016/0021-9517(92)90115-X, 136, 1, 161-169, 1992.01, The effect of oxide supports in hydrogenation of CO was investigated using Ru supported on metal oxides as catalysts. Activity for CO hydrogenation and product distribution depended on the electron affinity of the oxide supports. A support effect was also recognized in the adsorption state of hydrogen and carbon monoxide from temperature-programmed desorption (TPD) experiments. The support effect observed in this study seems to result from electronic interaction between Ru and support oxide, since the binding energy of Ru 3d 5 2 XPS peaks and the IR absorption frequency of linear-type NO depended on the electron affinity of the oxide support. The extent of charge transfer was represented by the electronegativity of support oxide in this study. The activity and the chain growth probability in CO hydrogenation are enhanced by using Ru on support oxides with high electronegativity because the deficient electron density of Ru weakened the CO adsorption and enhanced the concentration of hydrogen on catalyst surface..
556. Yusaku Takita, Takeshi Imamura, Yukako Mizuhara, Tatsumi Ishihara, HCN formation from CCI2F2 (CFC12) over iron group metal catalysts, Journal of Catalysis, 10.1016/0021-9517(92)90093-W, 136, 2, 617-620, 1992.01.
557. Tatsumi Ishihara, Kazuhiro Kometani, Yukako Mizuhara, Yusaku Takita, Mixed Oxide Capacitor of CuO—BaTiO3 as a New Type CO2 Gas Sensor, Journal of the American Ceramic Society, 10.1111/j.1151-2916.1992.tb07850.x, 75, 3, 613-618, 1992.01, An oxide capacitor consisting of BaTiO3 and an oxide is studied as a new type CO2 sensor based on capacitance change. Sensitivity to CO2, as well as the optimum operating temperature, was strongly dependent on the particular oxide mixed with BaTiO3. Among the elements investigated in this study, CuO–BaTiO3 exhibited the highest sensitivity to CO2. In particular, the CuO–BaTiO3 mixed oxide at the equimolar composition is highly sensitive to CO2. The optimum operating temperature and frequency for CuO–BaTiO3 are 729 K and 100 Hz, respectively, and the 80% response time to 2% CO2 is within 25 s. The equimolar mixture of CuO and BaTiO3 can measure the CO2 concentration from 100 to 60 000 ppm. Carbonation of oxide seems to play a key role for the detection of CO2 on these mixed oxide capacitors. The optimum operating temperature of these mixed oxide capacitors for CO2 detection, therefore, correlates with the decomposition temperature of the carbonate corresponding to the oxide mixed with BaTiO3. The capacitance increase of CuO–BaTiO3 upon exposure to CO2 seems to result from the elevated height of the potential barrier at the grain boundary between CuO and BaTiO3. Carbonation of CuO in the element seems to bring about the elevation in the height of the potential barrier..
558. Tatsumi Ishihara, Keiji Sato, Yukako Mizuhara, Yusaku Takita, Oxygen ion conductivity of yttria-niobia mixed oxide with fluoride related structure, Solid State Ionics, 10.1016/0167-2738(92)90223-C, 50, 3-4, 227-231, 1992.01, The oxygen ion conductivity of Y2O3Nb2O5 with a fluorite-like structure was studied. Substitutional solid solutions of Nb2 O5 in Y2O3 lattice formed the defect fluorite phase and remarkably enhanced the oxygen ion conductivity. Doping with tetravalent cations, especially Ti4+ or Ce4+, in yttria-niobia oxide is effective in enhancing the oxygen ion conductivity. Although the n-type semiconducting property appeared below PO2 = 10-18 atm at 1243 K, the yttria-niobia mixed oxide doped with Ce4+, Ti4+, and Zr4+ stably exhibited oxygen-ion conduction in the wide range of oxygen partial pressures studied..
559. Yusaku Takita, Shingo Kikukawa, Yumi Abe, Yukako Mizuhara, Tatsumi Ishihara, Partial Oxidation of Propane Over V—P—O Catalysts and Promoters, NIPPON KAGAKU KAISHI, 10.1246/nikkashi.1992.354, 1992, 4, 354-360, 1992.01, Over the catalyst containing (VO)2P2O7 and β∗-VOPO4, C3H8 was oxidized to acetic and acrylic acids with the selectivities of 30∼36% and 30∼38%, respectively. The addition of La2O3 and Dy2O3 onto the catalyst brought about an increase in the rate of carboxylic acids formation and its selectivity. The formation rate of the carboxylic acids gave a maximum at 10—20 at% of La content. Enhanced selectivity of carboxylic acids was observed upon the addition of Bi2O3. The selectivity of acetone extraporated to 0 sec of W/F was estimated to about 6%, suggesting that there is a reaction path to acetone via isopropenyl radical, isopropenylperoxyl radical. Temperature programmed desorption spectra of NH3 and C02 from the V—P—O catalysts with and without La2O3 indicated that the addition of La2O3 increased the amount of both weaker acidic sites and weaker basic sites. Comparing the formation rates of partial oxidation products over the La2O3 containing catalyst and that containing no La2O3 in the oxidation of C3H8, C3H6, and acrylic acid, it is concluded that added La2O3 mainly accelerates the rate of reaction via isopropenylperoxyl radical..
560. Tatsumi Ishihara, Yasuharu Watanabe, Yumi Abe, Yusaku Takita, CaSiO3 as a substrate material for Ba-Y-Cu-O superconducting oxide films, Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan, 10.2109/jcersj.100.298, 100, 1159, 298-302, 1992.01, The reactivities of Ba2YCu3O7-x with BaZrO3 and CaSiO3 were studied to develop a substrate material for superconducting oxide films. It was found that BaZrO8 and CaSiO2 were less reactive to Ba2YCu3O7-x and the onset critical temperature of Ba2YCu3O7-x remained unaltered after heating in contact with these materials at 1223 K. Although BaZrO2 was less reactive than CaSiO3, BaZrO3 was unsuitable for the substrate of Ba2YCu3O7-x films because of the large difference of the thermal expansion coefficient. On the other hand, the thermal expansion coefficient of CaSiO8 is almost the same as that of Ba2YCu3O7-x. High-Tc superconducting oxide films were prepared easily on the CaSiO3 substrate by the conventional dipping-pyrolysis method. As a result, mixed oxide, CaSiO2, is one of the promising materials for the substrate of Ba2YCu3O7-x films because of its low cost, low reactivity, and comparable in thermal expansion coefficient..
561. Tatsumi Ishihara, Kazuhiro Kometani, Yukako Mizuhara, Yusaka Takita, A new type of CO2 gas sensor based on capacitance changes, Sensors and Actuators: B. Chemical, 10.1016/0925-4005(91)80227-B, 5, 1-4, 97-102, 1991.08, Mixed oxides consisting of BaTiO3 and a metal oxide were studied as a new type of CO2 gas sensor based on capacitance changes. Small changes in the capacitance of a metal oxide caused by carbonation are amplified by mixing with BaTiO3, probably due to an enhancement of the barrier-layer capacitor. The CO2 sensing characteristics of mixed-oxide capacitors depend strongly on the operating frequency as well as on the operating temperature. Among the compositions investigated in this study, CuOBaTiO3 is the most sensitive to CO2. The combination CuOBaTiO3 selectively responds to carbon dioxide and can discriminate CO2 concentrations from 100 to 20 000 ppm..
562. Tatsumi Ishihara, Kazuhiro Kometani, Masayo Hashida, Yusaku Takita, Application of Mixed Oxide Capacitor to the Selective Carbon Dioxide Sensor
I. Measurement of Carbon Dioxide Sensing Characteristics, Journal of the Electrochemical Society, 10.1149/1.2085530, 138, 1, 173-176, 1991.01, Oxide capacitors consisting of BaTiO3 and an oxide are studied as a sensor for CO2 detection. Although the capacitance change of PbO on exposure to CO2 was small, it was greatly enhanced by the combination with BaTiO3. Sensitivity to CO2 and optimum operating temperature were strongly dependent on the oxide combined with BaTiO3. The element which contains basic oxides such as MgO and CaO, is highly sensitive to CO2, but the operating temperature exceeded 1073 K. Among the elements investigated in this study, CuO-BaTiO3 exhibited the highest sensitivity to CO2. CuO-BaTiO3 selectively responded to CO2, and this element could distinguish the CO2 concentrations up to 6%. On the other hand, the capacitance of NiO-BaTiO3 decreased linearly with increasing CO2 concentration up to 20%. Mixed oxide capacitors of CuO-BaTiO3 and NiO-BaTiO3, therefore, are suitable for sensing CO2 at the concentration range of hundreds of ppm, and at a percentage level, respectively..
563. Yusaku Takita, Hiroshi Yamada, Tatsumi Ishihara, Yukako Mizuhara, Catalytic Hydrodechlorination of CFC 113 (CCI2FCCIF2), NIPPON KAGAKU KAISHI, 10.1246/nikkashi.1991.584, 1991, 5, 584-590, 1991.01, Pd, Ni, Pt supported on TiO2 were effective for hydrodechlorination of CFC 113. The reaction took place at >150°C and C2H2F2, C2F3C1 and C2H2F2 and C2H3F3 were formed over the catalysts, respectively. C2F3C1 was formed over Co/Ti02 at 350 °C and the same reaction took place over MnTiO3 at >500°C. Pd/C tends to substitute hydrogen atoms for chlorine atoms so that CF2HCFH2 was formed from CFC 113 with high selectivity of more than 85%. The activities of Rh/C and Pt/C were smaller than that of Pd/C. The addition of 2 mol% of water vapor did not affect the reaction but supressed the formation of CH4 and promoted the formation of CO at>300°C. Plots of the catalytic activity against the heat of formation of metal chlorides gave a volcano shape. This suggests that the reaction proceeded via chlori-nation and dechlorination of the catalyst surface. MnTi03 was so stable that XRD pattern decreased slightly in intensity after the CFC 113-H2 reaction for 25 h at 550 °C. The structure of Cr2O3 was not changed after the reaction at 350 °C for 20 h by XRD..
564. Tatsumi Ishihara, Hideharu Iwakuni, Koichi Eguchi, Hiromichi Arai, Hydrogenation of carbon monoxide over the mixed catalysts composed of cobalt-nickel/manganese oxide-zirconium oxide and zeolite catalysts, Applied Catalysis, 10.1016/S0166-9834(00)83133-4, 75, 1, 225-235, 1991.01, Mechanical mixtures of Co-Ni/MnO-ZrO2 and zeolite were used as catalysts for the selective synthesis of gasoline by carbon monoxide hydrogenation. Formation of branched alkanes was promoted, but that of hydrocarbons higher than a carbon number of 10 was suppressed by a combination with zeolite. The reactivity of zeolite for higher hydrocarbons has the decisive role in the product distribution on these mixed catalysts, and thus the product distribution strongly depended on the type of zeolite. Since the hydrogenolysis of higher hydrocarbons proceeds on the strong acid sites, the formation of branched alkanes was promoted by increasing the aluminium content in the zeolite. Ammonia temperature-programmed desorption suggests that increasing the aluminium content in the zeolite increases the number of strong acid sites, but weakens the average strength of the acid sites. Pentasil zeolite with an aluminium content of 1.32 mmol g-1 is effective for enhancing the yield of gasoline as well as its octane number..
565. Yusaku Takita, Katsuyoshi Tanaka, Shiro Ichimaru, Tatsumi Ishihara, Takanori Inoue, Hiromichi Arai, Location and functions of Zn as a promoter element in the VPO catalysts for n-butane oxidation to maleic anhydride, Journal of Catalysis, 10.1016/0021-9517(91)90118-N, 130, 2, 347-353, 1991.01, Location of zinc in the VP0 catalysts containing zinc was examined along the preparation process. The mixture of H4(VO)2P209, (NH4)2ZnCl4, and NH4ZnPO4 was formed, when an aqueous solution containing VO2+, Zn2+, and NH30HCI was evaporated to dryness. TG-DTA results of the mixture revealed that (NH4)2 ZnCl4 decomposed to ZnO at 470-570 K and water molecules were eliminated from H4(VO)2P209 to give (VO)2P207 at 670-700 K, then the solid phase reaction between (VO)2P207 and ZnO took place at 790-810 K without any loss of the weight. Addition of 10 at.% of ZnO addition to (VO)2P207 by mechanical mixing brought about drastic increase in the oxidation rate of the catalyst to VOP04. This may be responsible for the increase in the rate of catalytic n-butane oxidation without significant changes in the product distribution observed over the Zn-promoted VP0 catalysts..
566. Yukako Mizuhara, Masao Noguchi, Tatsumi Ishihara, Atsushi Satoh, Katsuto Hiramatsu, Yusaku Takita, Preparation of Fiberlike Silicon Nitride from Diatomaceous Earth, Journal of the American Ceramic Society, 10.1111/j.1151-2916.1991.tb06936.x, 74, 4, 846-848, 1991.01, Fiberlike Si3N4 was prepared by the carbothermal reduction of diatomaceous earth in a flow of nitrogen and ammonia. Diatomaceous earth, which is an inexpensive raw material, is composed of 82.5 wt% SiO2, 5.69 wt% Al2O3, and a very small amount of metal oxides (K2O, CaO, and Fe2O3). Two types of fiberlike Si3N4 were obtained, short needlelike fiber and woollike fiber with Fe droplets at 1350°C..
567. Tatsumi Ishihara, Nobuhiko Horiuchi, Koichi Eguchi, Hiromichi Arai, The effect of supports on the activity and selectivity of CoNi alloy catalysts for CO hydrogenation, Journal of Catalysis, 10.1016/0021-9517(91)90104-C, 130, 1, 202-211, 1991.01, The CO hydrogenation activity of 50Co50Ni alloy catalysts strongly depended on the oxide support. Electron-donating oxides such as MgO, PbO, and ZnO lowered the overall activity of the 50Co50Ni metal. The CO conversion as well as the chain growth probability was high over 50Co50Ni/TiO2 and 50Co50Ni/MnO2. The infrared spectra of adsorbed NO indicated that the electron density of the 50Co50Ni metal was low when it was supported on electron-accepting oxide. The results of desorption measurements suggest that metal-support interaction has a great influence on the surface concentration of hydrogen and carbon monoxide, and adsorption of carbon monoxide and hydrogen is weakened by increasing the electronegativity of the oxide support. Since the rate of H2D2 exchange correlated well with the CO hydrogenation rate, activation of hydrogen is of primary importance in this catalyst system. The low electron density of the alloy supported on the electron-accepting oxides such as TiO2 and SiO2 weakens CO adsorption, resulting in an increase in surface coverage of hydrogen. Thus sufficient coverage of hydrogen leads to a high CO hydrogenation rate..
568. Tatsumi Ishihara, Hideharu Iwakuni, Koichi Eguchi, Hiromichi Arai, Hydrogenation of Carbon Monoxide over Mixed Catalysts Composed of Co-Ni/MnO-ZrO2 and Zeolite, NIPPON KAGAKU KAISHI, 10.1246/nikkashi.1990.711, 1990, 7, 711-718, 1990.01, The mechanical mixtures of Co-Ni/MnO-ZrO2 and zeolite were used as catalysts for the selective synthesis of gasoline by CO hydrogenation. Formation of branched-paraffins was promoted but that of higher hydrocarbons than carbon number of 10 was suppressed by combination with zeolite. The product distribution strongly depended on the type of zeolite catalyst. Pentasil zeolite was active for the formation of branched-paraffins, probably because of the cracking reaction occurring on the strong acid sites. The formation of branched-paraffins was further promoted by ion-exhange with Pt. The mixture of Co-Ni/MnO-ZrO2 and PtH-pentasil zeolite was very active for the formation of gasoline with high octane number..
569. Yusaku Takita, Tatsumi Ishihara, Masayo Hashida, A new HCN production from CCl2F2 (CFC12) and ammonia over NiTiO3, Ni metal, and Pt/C catalysts, Journal of the Chemical Society, Chemical Communications, 10.1039/C39900001247, 18, 1247-1248, 1990.01, NiTiO3, Ni metal, and Pt/C are effective catalysts for the formation of HCN from CFC12 and NH3 at 673-823 K: 86.2% yield is attained at 723 K over Ni metal..
570. Tatsumi Ishihara, Nobuhiko Horiuchi, Koichi Eguchi, Hiromichi Arai, Hydrogenation of carbon monoxide over cobalt-nickel alloy catalyst supported on MnO-ZrO2 mixed oxide, Applied Catalysis, 10.1016/S0166-9834(00)81644-9, 66, 1, 267-282, 1990.01, Hydrogenation of carbon monoxide was studied over mixed oxide supported 50Co50Ni alloy catalysts. The activity as well as the selectivity for carbon monoxide hydrogenation is strongly affected by the oxide support. The mixed oxides containing ZrO2, CeO2, and Nb2O5 promoted the carbon monoxide hydrogenation over 50Co50Ni, but those containing MgO or ZnO lowered the overall activity of Co-Ni alloy. The product distribution on the alloy catalyst supported on ZrO2-Nb2O5, Nb2O5-V2O5, MnO-ZrO2 and MnO-V2O5 deviated from the Schulz-Flory distribution owing to the high yield of gasoline. In particular, the formation rate of gasoline on Co-Ni/MnO-ZrO2 amounts to 9.87·10-3 mol h-1 g-1 at 548 K. Mixing MnO with ZrO2 forms electronic unsaturated sites and the mixed oxide support interacts electronically with the Co-Ni alloy through these electronic unsaturated sites. The electronic density of Co-Ni alloy depends on the kind of mixed oxide and its composition. A support effect was recognized in the adsorption state of hydrogen and carbon monoxide..
571. Tatsumi Ishihara, Kazuhiko Shiokawa, Koichi Eguchi, Hiromichi Arai, The mixed oxide A12O3V2O5 as a semiconductor gas sensor for NO and NO2, Sensors and Actuators, 10.1016/0250-6874(89)87078-7, 19, 3, 259-265, 1989.09, Several semiconductive oxides are tested as sensors for the detection of NO, NO2, CO and CO2. The conductivity of Al2O3V2O5 is sensitive to 1-1000 ppm of NO and NO2, but is insensitive to CO or CO2. The mixed oxide (Al2O3)0.5(V2O5)0.5 is excellent not only in its selectivity for detection of NO and NO2 but also in its sensitivity. The amount of NO adsorbed is greatly enhanced, but that of CO is unaffected by mixing V2O5 with Al2O3. The high sensitivity of Al2O3V2O5 to NO and NO2 appears to result from the increased amount of adsorbed nitrogen oxide..
572. Tatsumi Ishihara, Nobuhiko Horiuchi, Koichi Eguchi, Hiromichi Arai, Hydrogenation of Carbon Monoxide over Cr-, Mo-, and Mn-added Fe-Co-Ni Alloy Catalysts, NIPPON KAGAKU KAISHI, 10.1246/nikkashi.1989.193, 1989, 2, 193-198, 1989.01, Carbon monoxide hydrogenation activity over TiO2-or SiO2-supported Fe—Co—Ni alloy decreased with addition of Cr, Mo, or Mn due to suppressed adsorption of hydrogen and carbon monoxide on the alloy surface. However the selectivity to oxygenated compounds such as ethanol or acetone was enhanced over Cr-and Mo-added Fe—Co—Ni alloy. On the other hand, the chain growth probability was promoted over Mn added 50 Co 50 Ni. Since the vibrational frequency of adsorbed NO shifted to higher wavenumbers, the electron density of Fe—Co—Ni alloy seems to be lowered by the addition of Cr, Mo, and Mn. Dissociative chemisorption of CO is suppressed on electron deficient surface of the Fe—Co—Ni alloy, resulting in high selectivity to oxygenated compounds..
573. Tatsumi Ishihara, Koichi Eguchi, Hiromichi Arai, Supported iron-cobalt-nickel ternary alloy catalysts for the hydrogenation of carbon monoxide, Applied Catalysis, 10.1016/S0166-9834(00)80428-5, 40, C, 87-100, 1988.01, Supported ternary alloy catalysts of iron, cobalt, and nickel for carbon monoxide hydrogenation were studied systematically. Alloying of these metal components mostly enhanced the catalytic activity and suppressed methanation. The alloy catalyst of 50Co50Ni yielded a large amount of gasoline compounds; and the cobalt-rich iron-cobalt system was selective for olefin formation. The increase in iron content lowered the overall catalytic activity and accelerated methanation. The affinities of the metal surfaces to hydrogen and carbon monoxide adsorption appear to be affected by alloying, resulting in a change in the ratio of active hydrogen to carbon monoxide on the surface. The catalytic activity of supported iron-cobalt-nickel ternary alloy catalyst was largely determined by the amount of active hydrogen..
574. Tatsumi Ishihara, Koichi Eguchi, Hiromichi Arai, Hydrogenation of carbon monoxide over SiO2-supported FeCo, CoNi and NiFe bimetallic catalysts, Applied Catalysis, 10.1016/S0166-9834(00)84115-9, 30, 2, 225-238, 1987.01, Hydrogenation of carbon monoxide was studied at 523 K under 1.0 MPa over SiO2-supported bimetallic catalysts. The activities of SiO2-supported bimetallic catalysts of FeCo, CoNi and NiFe for CO hydrogenation were greater than those of monometal catalysts. The product distribution was shifted to the higher hydrocarbons by alloying of metals. The SiO2-supported bimetallic catalysts were slightly less active than TiO2-supported ones; the product distribution was not affected by the support. Olefins, paraffins and gasoline compounds were produced selectively on FeCo, NiFe and CoNi bimetallic catalysts, respectively. The cobalt-nickel system is particularly suitable for catalytic gasoline synthesis because this catalyst is most selective for formation of higher hydrocarbons as well as most active for CO conversion. It is clear that alloying affects the adsorption ability of hydrogen and carbon monoxide, resulting in a change in the ratio of activated hydrogen and carbon monoxide on the surface..
575. Tatsumi Ishihara, Hiromichi Arai, Tetsuro Seiyama, Alkylation of Toluene over Zeolite Catalysts, journal of the japan petroleum institute, 10.1627/jpi1958.28.463, 28, 6, 463-469, 1985.01, Alkylation of toluene has been studied extensively, and as a result, the ortho/para orientation of substit-uents has been established. However, isomerization under its own containing reaction conditions always resulted in a mixture containing xylene isomer in a thermodynamical equilibrium, i.e., 24% para isomer, 55% meta isomer, and 21% ortho isomer. Zeolite catalysts, which possess shape selective characteristics, are expected to produce higher concentration of para-xylene than that in equilibrium by selective toluene alkylation with methanol. Thus, such selective alkylation has been studied extensively.2),6) One of the objectives of this study is to find a practical method for alkylation of toluene with methanol or ethanol to produce high yields of para-xylene or para-ethylto-luene. The catalysts used in this study are shown in Table 1. Prior to reaction, Na+ of the zeolites was exchanged with H+, and the catalysts were calcined at 673K for 4h. Activities and selectivities of these catalysts were evaluated in a fixed bed flow reactor of atmospheric pressure. The feed stream was a mixture of N2, toluene and methanol or ethanol (N2: toluene + methanol or ethanol=9 : 1). Runs were normally carried out at 523K. W/F was usually 10g-cat.h/mol, where W is the catalyst weight (gram) and F is the total flow rate (moles per hour). Product distribution was analyzed with gas chromatography. Based on the results of alkylation over a variety of zeolites (Fig. 3), pentasil zeolite exhibited both catalytic activity (toluene conversion> 10%) and para-xylene isomer selectivity (≃30%). It was evident that the shape selective characteristics of zeolites were dependent on their effective pore size and acidity (Figs. 4, 5, 6), i.e., zeolites that have smaller pore sizes and lower Al contents exhibited higher selectivities for para-isomer. It was reported13) that the shape selective characteristics of zeolites could be enhanced by selective poisoning of their outer surface acid sites. Therefore, such selective poisoning was attempted using 2,4-dimethyl quinoline (Fig. 9), which, because of its effective molecular size, cannot enter the zeolite pores. However, based on the absence of para isomer selectivity observed, the shape-selective characteristics of the zeolites were not affected by mere selective poisoning of their outer surface acid sites. It is well-known3),5) that modification of pentasil zeolite by phosphorus or boron enhances the shape-selective characteristics because of the decrease in the size of the pores and number of strong acid sites. The modification of pentasil by impregnation with a phosphorus compound or boron compound also enhances para isomer selectivity (Figs. 10 and 11). Para xylene selectivity was more than 40% on these modified pentasil zeolite catalysts, while it was about 30% on untreated pentasil zeolite. However, offretite/eri-onite zeolite, whose pore size is nearly equal to that of pentasil zeolite, was not effective, even when it was modified with phosphorus. Compared with methyla-tion of toluene, ethylation of toluene exhibited greater shape selective characteristics (Fig. 12). In the ethylation of toluene, the untreated pentasil zeolite dispro-portionates toluene to produce dominantly benzene and xylenes, and produces only a small amount of ethyl-toluene nearly in the equilibrium para-isomer composition (26%). On the other hand, the modified pentasil zeolite produces more than 70% para isomer in ethyltoluene but scarcely any ortho isomer..