2025/04/15 更新

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写真a

マツシマ シゲノリ
松嶋 茂憲
MATSUSHIMA SHIGENORI
所属
総合理工学研究院 連携融合理工学部門 教授
職名
教授

経歴

  • 九州大学 工学部 客員教授 

    2023年4月 - 2024年3月

  • 九州工業大学 生命体工学研究科生体機能専攻 客員教授(精密環境計測講座担当) 

    2009年4月 - 2015年3月

  • ドイツ連邦共和国,ギーセン大学  在外研究員 

    2008年7月 - 2008年8月

研究テーマ・研究キーワード

  • 研究テーマ: Industrial Physical Chemistry

    研究キーワード: Industrial Physical Chemistry

    研究期間: 2024年

  • 研究テーマ: Electronic Structure

    研究キーワード: Electronic Structure

    研究期間: 2024年

受賞

  • 功労賞

    2015年   北九州工業高等専門学校  

論文

  • Effect of Al co-doping on the phase transition of V-doped ZrO2 査読 国際誌

    R. Kaminaga, K. Obata, S. Matsushima, T. Suzuki

    Journal of the Ceramic Society of Japan   131 ( 6 )   181 - 187   2023年6月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.2109/jcersj2.23006

  • Effect of M-doping (M = Al, Y, La) on the electronic structure of V-doped ZrO<sub>2</sub>: A first-principles study 査読 国際誌

    Kouki Nakamura, Shigenori Matsushima, Junko Ishii, Masao Arai, Kenji Obata

    Journal of the Ceramic Society of Japan   130 ( 12 )   925 - 932   2022年12月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Ceramic Society of Japan  

    DOI: 10.2109/jcersj2.22101

  • Rational design of Cu-doped ZnS nanospheres for photocatalytic evolution of H2 with visible light (accepted) 査読 国際誌

    Xin Liu, Ya Zhang, Shigenori Matsushima, Takeharu Sugiyama, Hajime Hojo, Hisahiro Einaga

    ACS Applied Energy Materials   5 ( 2 )   1849 - 1857   2022年   eISSN:2574-0962

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Photocatalytic reactions to produce hydrogen from water under visible-light irradiation are an important key process for solar energy utilization. Because Cu-doped ZnS undergoes redox reactions upon irradiation with visible light, these materials have been applied to hydrogen production. In this study, Cu-doped ZnS catalysts were prepared by a solvothermal method, and their structures were investigated using scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, and ultraviolet-visible spectroscopic studies. Cu-doped ZnS consists of nanospherical particles with a diameter of 50 nm. Cu2+ doping in ZnS causes structural distortion of the ZnS. The local structures were analyzed by X-ray absorption fine structure studies. As the amount of Cu added to ZnS increased, the degree of distortion of the ZnS structure also increased, and this degree of distortion reached a maximum when the Cu/Zn ratio was 0.07 (7% Cu doping). Cu-doped ZnS exhibited high activity in the hydrogen production reaction from water using Na2S and Na2SO3 as sacrificial agents under visible-light irradiation (λ > 420 nm), and the highest activity was observed at 7% Cu doping.

    DOI: 10.1021/acsaem.1c03323

    Scopus

  • First-principles energy band calculation of Pr-doped ZrSiO4 査読 国際誌

    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN   129 ( 12 )   764 - 769   2021年12月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Fabrication and characterization of La-added MgFe2O4 as catalyst support for CO oxidation 査読 国際誌

    Akane Doi, Kenji Obata, Shigenori Matsushima, Hajime Hojo, Hisahiro Einaga

    Ceramics International   47 ( 23 )   32786 - 32793   2021年   ISSN:0272-8842

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Elsevier BV  

    DOI: 10.1016/j.ceramint.2021.08.175

  • CO sensing properties of La-added MgFe2O4 powders 査読 国際誌

    Kenji Obata, Shigenori Matsushima

    Sensors and Materials   33 ( 9 )   3213 - 3213   2021年   ISSN:0914-4935 eISSN:2435-0869

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MYU K.K.  

    DOI: 10.18494/sam.2021.3446

  • Electronic structure and optical properties of Y2BaCuO5 with antiferromagnetic spin arrangements 査読 国際誌

    Shigenori Matsushima, Masao Arai, Junko Ishii, Kouki Nakamura

    Journal of the Ceramic Society of Japan   128 ( 12 )   1055 - 1060   2020年12月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    First-principles energy band calculations are performed for Y2BaCuO5 (YBC211) with ferromagnetic and three types of antiferromagnetic (AFM) spin orderings, namely, A, C, and G. The most stable phase is found to be G AFM ordering (AFM_G_YBC211). The calculated magnetic moment at the Cu sites is almost identical to the experimental one reported in the literature. However, the energy bandgap is estimated to be only 035 eV. The valence band (VB) maximum locates on the S-Gamma line and the conduction band (CB) minimum locates at the Gamma point, suggesting that AFM_G_YBC211 is an indirect bandgap oxide. From the density-of-states analysis, the VB of AFM_G_YBC211 comprises mainly the Cu 3d and 0 2p states. The lower CB comprises the Cu 3d states, whereas the upper CB is attributed mainly to the Y 4d, Ba 5d, and O 2p states. Furthermore, in the dielectric function calculation of AFM_G_YBC211, the epsilon(2)(omega) curves exhibit very strong peaks for the yy and zz components at 0.87 eV, whereas the corresponding peak for the xx component is weak. This difference is attributed to the anisotropy of the momentum matrix elements between the VB and the lower CB. (C) 2020 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.20154

    Web of Science

  • Photocatalytic oxidation process for treatment of gas phase benzene using Ti3+ self-doped TiO2 microsphere with sea urchin-like structure 査読 国際誌

    Chemical Engineering Journal   128   126220   2020年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • First-principles energy band calculation of a (Ca2+, V5+)-doped Y2Ti2O7 pigment 査読 国際誌

    Shigenori Matsushima, Yuya Tanaka, Junko Ishii, Kenji Obata

    Journal of the Ceramic Society of Japan   127 ( 11 )   1 - 9   2019年11月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    A first-principles energy band calculation is performed with respect to the V5+- and (Ca2+, V5+)-doped Y2Ti2O7 supercells to elucidate the effect of Ca2+ doping on the electronic structure and optical properties of a V5+-doped Y2Ti2O7 pigment in the present study. The structural optimization calculation reveals that the theoretical lattice constant of the Y2Ti2O7 unit cell slightly increases when compared with that in the experimental data. The forbidden gap at the r point is estimated to be 2.78 eV. On the basis of the density-of-states analysis, the valence band (VB) of Y2Ti2O7 mainly comprises the O 2p states and hybridizes with the Ti 3d and 4d states. The conduction band (CB) can be divided into two energy regions. The lower CB comprises the Ti 3d states and hybridizes with the O 2p states, whereas the upper CB comprises the Y 4d, Ti 3d, and O 2p states. When Y2Ti2O7 is doped with a V atom, the VB width and bandgap are observed to expand by 0.7 and 0.2 eV, respectively, with respect to the pristine Y2Ti2O7. Two strongly localized peaks, corresponding to the V 3d states, appear in the bandgap. Further, three strongly localized peaks appear in the bandgap when V5+-doped Y2Ti2O7 is doped with a Ca atom. In the dielectric function calculation of the V5+-doped Y2Ti2O7, there is broad absorption from the O 2p VB states to the V 3d gap states as well as a VB-CB optical transition in the host crystal. When the V5+-doped V2Ti2O7 is doped with a Ca atom, the distortion of the VO6 octahedron becomes large, leading to an increment of 0 2p state densities near the valence-band maximum of the host. Thus, it is considered the momentum matrix elements between occupied states (O 2p states) and unoccupied states (V 3d states) becomes large in comparison with the case before a Ca doping. (C) 2019 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.19103

    Web of Science

  • Experimental and theoretical approaches for the investigation of proton conductive characteristics of La1-xBaxYbO3-δ 査読 国際誌

    Yuki Obukuro, Yuji Okuyama, Go Sakai, Shigenori Matsushima

    Journal of Alloys and Compounds   770   294 - 300   2019年1月   ISSN:0925-8388 eISSN:1873-4669

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    proton conductive characteristics of La1-xBaxYbO3-delta (x=0.02, 0.06, 0.10) were examined by an impedance analysis in the temperature range of 873-1473 K. The maximum proton concentrations in La1-xBaxYbO3-delta determined by the weight changes were almost 1/5 of the oxygen vacancies formed by the substitution of Ba. This result indicated that at least two types of oxygen vacancies, a hydratable oxygen vacancy and hydration independent one, exist in the crystal. The bond distances and electronic structure of the Ba-substituted LaYbO3 supercell with or without an oxygen vacancy were investigated by the first-principles molecular dynamics calculations. The substitution of Ba for the La-site of LaYbO3 was found to induce the local structure change of oxygen atoms surrounding the La atom. (C) 2018 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jallcom.2018.08.062

    Web of Science

  • Electronic structures and optical properties of CuMgVO4 and AgMgVO4: A first-principles study 査読 国際誌

    Tomoya Gake, Shigenori Matsushima, Masao Arai, Kenji Obata

    Journal of the Ceramic Society of Japan   127 ( 1 )   1 - 6   2019年1月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    Electronic structures and optical properties of CuMgVO4 and AgMgVO4 with optimized structures were investigated using the generalized gradient approximation proposed by Perdew-Burke-Ernzerhof and the Heyd-Scuseria-Ernzerhof hybrid functional. From the energy band calculation, we found that CuMgVO4 and AgMgVO4 have indirect band gaps. The upper valence band is mainly composed of fully occupied Cu 3d (Ag 4d) states, and the lower is mainly comprises O 2p states. The conduction band can be divided into two regions because of the crystal-field splitting by the interaction between the V 3d and the O 2p states. The optical properties of CuMgVO4 and AgMgVO4 were predicted from the complex dielectric function, epsilon(omega) = epsilon(1)(omega) + i epsilon(2)(omega). The static dielectric constants were estimated from the real part of the dielectric functions, epsilon(1)(omega). The imaginary part of the dielectric functions, epsilon(2)(omega), demonstrated optical anisotropy, with the component along the z (y) direction being larger than the others for CuMgVO4 (AgMgVO4) in the wavelength range of visible light. The absorption coefficient I(omega) was also calculated from the dielectric function. (C) 2019 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.18167

    Web of Science

  • Electronic and structural properties of H-intercalated graphene-SiC (0001) interface 査読 国際誌

    Junko Ishii, Shigenori Matsushima, Masamichi Naitoh

    Japanese Journal of Applied Physics   58 ( 3 )   35001   2019年   ISSN:0021-4922 eISSN:1347-4065

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

    In this study, we investigate the changes in electronic and structural properties of a graphene layer deposited on a (root 3 x root 3) R30 degrees SiC (0001) surface before and after hydrogen intercalation using first-principles energy band calculations. Before hydrogen adsorption, the bond distance between the first graphene layer (FGL) and an Si atom on SiC surface is calculated to be 0.2285 nm, which is close to the value reported in the literature. After hydrogen adsorption, the layer distance between SiC surface and FGL tends to increase. The adsorption energy of hydrogen on SiC surface as estimated from the total energy change before and after hydrogen adsorption is relatively small. Thus, we suggest that hydrogen easily bonds to Si dangling bonds on SiC surface. When Si dangling bonds on SiC surface are passivated by hydrogen, the graphene layer on SiC functions as a quasi-free-standing graphene layer, whether the graphene exfoliates or not. Therefore, our results indicate the effectiveness of the hydrogen intercalation technique to create quasi-free-standing epitaxial graphene on Si-face SiC (0001) substrate. (C) 2019 The Japan Society of Applied Physics

    DOI: 10.7567/1347-4065/aafb4a

    Web of Science

  • Morphology, microstructure, and surface area of La-added MgFe2O4 powder 査読 国際誌

    Journal of the Ceramic Society of Japan   126   1 - 6   2018年1月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • CO2 sensing properties of Zr-added CaFe2O4-based sensor 査読 国際誌

    International Training Institute for Materials Science   271 - 273   2017年11月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

  • First-principles study on LaYbO3 as the localized f electrons containing system with MBJ-LDA plus U approach 査読 国際誌

    Yuki Obukuro, Kakeru Ninomiya, Masao Arai, Yuji Okuyama, Go Sakai, Shigenori Matsushima

    Computational Materials Science   126   7 - 11   2017年1月   ISSN:0927-0256 eISSN:1879-0801

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    The electronic structure of LaYbO3 was investigated by the full potential linearized augmented plane wave plus local orbital (FLAPW + lo) method with the modified Becke-Johnson potential combined with the local density approximation correlation plus onsite Coulomb interaction (MBJ-LDA + U) for the sake of localized f electrons. This approach was suitable for evaluating electronic structure of LaYbO3 system from view point of calculation cost and time. The band gap, the difference in energy between the valence band (VB) and conduction band (CB), was estimated to be 6.0 eV by the present method. The evaluated value was very close to the reported experimental value. In the VB, Yb 4f orbitals and O 2p orbitals were well hybridized each other to state predominantly. The lower potential region in CB was mainly composed of La 4f orbitals, while the upper region in CB was mainly consisted of La 5d orbitals. (C) 2016 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.commatsci.2016.09.005

    Web of Science

  • Growth of p-type ZnOS films by pulsed laser deposition 査読 国際誌

    Journal of Crystal Growth   457   289 - 293   2017年1月   ISSN:0022-0248 eISSN:1873-5002

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    ZnO1-xSx films were deposited on quartz substrates by pulsed laser deposition (PLD) of ZnO1-xSx targets. The ZnO1-xSx films with S-contents of 0.03-0.17 were grown from the ZnO1-xSx targets sulfured at temperatures of 200 and 500 degrees C. The resistivity of the ZnO1-xSx films is slightly increased with the S-content. An increase of the O-2-partial pressure in an atmosphere reduces the S-content in the films and drastically enhances the resistivity of the films. However, the carrier type of the films is still n-type. In order to incorporate excess S atoms into films, evaporation of Sulfur was performed during the PLD process. As a temperature of the S-evaporation is raised, the resistivity of the films is significantly enhanced and hole-conductivity appears in the films grown by the S-evaporation at 80 and 90 degrees C. By Xray photoelectron spectroscopic measurements, the presence of SOx species is confirmed for the p-type ZnO1-xSx film. Both interstitial SO3 or SO4 clusters and complexes of Zn-vacancy with H are considered to be appropriate acceptors responsible for the hole-conductivity at room temperature. (C) 2016 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jcrysgro.2016.06.029

    Web of Science

  • First-principles calculation of M3Ta6Si4O26 (M = Ba, Sr) using Tran–Blaha exchange Potential 査読 国際誌

    Tomoya Gake, Kakeru Ninomiya, Kenji Obata, Masao Arai, Shigenori Matsushima

    Journal of the Ceramic Society of Japan   125 ( 7 )   574 - 578   2017年   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    The first-principles energy band calculation for M3Ta6Si4O26 (M = Ba, Sr) with optimized structure is performed using the Tran-Blaha (TB) exchange potential combined with correlation potential from the local density approximation (LDA). The theoretical minimum band gaps of Ba3Ta6Si4O26 and Sr3Ta6Si4O26 are estimated to be 4.39 and 4.46 eV, respectively. These results are in large contrast to the underestimation based on the generalized gradient approximation calculation. The band gaps of M3Ta6Si4O26 (M = Ba, Sr) hardly changed with the spin-orbit interaction. The main conduction band can be divided into two energy regions near 7.6 eV due to the octahedral crystal-field splitting based on the interaction between Ta-d and O-p states. On the other hand, the main valence band in the energy range of -5.3 to 0 eV is constructed from O-p states, where the Ta-d states hybridize strongly with the O-p states. The optical properties of M3Ta6Si4O26 (M = Ba, Sr) are predicted from the complex dielectric function epsilon(omega) = epsilon(1)(omega) + i epsilon(2)(omega). Polarized peaks in the z-direction appear at 5.5 and 6.4 eV for Ba3Ta6Si4O26, 5.6 and 6.6 eV for Sr3Ta6Si4O26 in the epsilon(2)(omega) function, respectively. The absorption coefficient estimated from the TB-LDA is very similar to the experimental result obtained in the literature. (C)2017 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.17046

    Web of Science

  • Micronization of MgFe2O4 particles doped with Si 査読 国際誌

    Journal of the Ceramic Society of Japan   124 ( 7 )   777 - 780   2016年7月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    The effect of Si addition was studied for the purpose of the improvement of microstructure of MgFe2O4 particles prepared from a malic acid complex. There were no traces of any impurity phase in Si-doped and pure MgFe2O4 powders both in XRD measurements. When Si atoms were doped to MgFe2O4, crystallite growth of MgFe2O4 was remarkably suppressed, and the lattice volume increased up to 10 mol% Si monotonously. SEM observations revealed that MgFe2O4 powders show a granulation shape such as the aragonite and each particle tightly interconnected each other, whereas smaller particles compared with pure MgFe2O4 were observed for Si-doped MgFe2O4. Also, it was found that the amount of mesopore increases by Si doping. Further, XPS and XAS measurements suggested that Si atoms exist in MgFe2O4 crystal. (C) 2016 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.16042

    Web of Science

    J-GLOBAL

  • Electronic structure of photoresponsive Ag6M2O7 (M = Si, Ge) 査読 国際誌

    Journal of the Ceramic Society of Japan   124 ( 1 )   116 - 121   2016年1月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    The electronic structures of Ag6M2O7 (M = Si, Ge) are investigated by the scalar-relativistic full potential linearized augmented plane wave plus local orbital (FLAPW+lo) method using the modified Becke-Johnson (MBJ) potential combined with the local density approximation (LDA) correlation. For Ag6M2O7 (M = Si, Ge), the valence band maximums (VBM) are approximately located at the X (Si) or A (Ge) and the conduction band minimums (CBM) at the Gamma both, indicating that Ag6M2O7 are an indirect energy gap material. The fundamental band gaps of Ag6Si2O7 and Ag6Ge2O7 are calculated to be 1.69 and 1.42 eV, respectively, in the MBJ-LDA calculation. The results are a remarkably contrast to the underestimation based on the generalized gradient approximation (GGA) calculation. On the other hand, there is no distinct difference in the effective masses of photogenerated holes and electrons near the VBM and CBM between MBJ-LDA and GGA approaches. The optical properties of Ag6M2O7 (M = Si, Ge) are contemplated from spectral dependence of the complex dielectric function, epsilon (omega) = epsilon(1) (omega) + i epsilon(2) (omega). (C) 2016 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.15208

    Web of Science

    J-GLOBAL

  • First-principles calculation study of epitaxial graphene layer on 4H-SiC (0001) surface 査読 国際誌

    e-Journal of Surface Science and Nanotechnology   14   121 - 124   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Effect of La doping on structural, optical, electronic properties of Sr2Bi2O5 photocatalyst 査読 国際誌

    Yuki Obukuro, Shigenori Matsushima, Kenji Obata, Takuya Suzuki, Masao Arai, Eiji Asato, Yuji Okuyama, Naoki Matsunaga, Go Sakai

    Journal of Alloys and Compounds   658   139 - 146   2016年   ISSN:0925-8388 eISSN:1873-4669

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    Single-phase Sr2Bi2O5 was obtained by calcination of the heterobimetallic complex precursor Sr [Bi(DTPA)]center dot 9H(2)O (DTPA is diethylenetriaminepentaacetic acid) at 700 degrees C for 6 h. The effect of La doping on the crystal structure, surface area, morphology, surface chemical state, and absorption properties of Sr2Bi2O5 samples prepared from Sr[Bi(DTPA)]center dot 9H(2)O were investigated. No traces of an impurity phase were detected in samples with a lower La content (3 and 5 mol%), while impurity phases such as Sr2Bi2O5 and SrCO3 were observed in Sr2Bi2O5 samples with larger La contents of 8 and 10 mol%. The Brunauer-Emmett-Teller surface area of Sr2Bi2O5 increased slightly with the content of La. High-resolution transmission electron microscopy revealed clear crystalline planes for both undoped and La-doped Sr2Bi2O5 samples without amorphous phases. Meanwhile, X-ray photoelectron spectroscopy indicated that the valence states of constituent metals were Sr2+, Bi3+, and La3+. The solubility limit of La in the Sr2Bi2O5 crystal phase was determined from Raman scattering measurements. La atoms substituted Bi sites when the doping content was low, while both Bi and Sr sites were substituted with La when the content of La was high. The electronic structure of Sr2Bi2O5 could be modified by La doping, resulting in a red shift of the absorption edge with increasing La content. The band-gap narrowing of Sr2Bi2O5 with La-doping was reproduced in energy-band calculations. The photocatalytic activity of Sr2Bi2O5 under visible-light irradiation for the oxidation of isopropanol was enhanced by doping with La. (C) 2015 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jallcom.2015.10.199

    Web of Science

    J-GLOBAL

  • CO2 Sensing Properties of Zr-Added Porous CaFe2O4 Powder 査読 国際誌

    Sensors and Materials   28 ( 11 )   1157 - 1164   2016年   ISSN:0914-4935

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MYU, SCIENTIFIC PUBLISHING DIVISION  

    The gas sensing properties of Zr-added and pure CaFe2O4 powders for CO2 in air were examined in the temperature range of 250-450 degrees C. The semiconductor-type gas sensor made from pure CaFe2O4 powder showed a fairly good response to CO2. Furthermore, the addition of a small amount of Zr into CaFe2O4 powder was found to be effective for enhancing the CO2 response of the present gas sensor. It was also found that the gas response, defined by the ratio of the resistance in air and that of the target gas reached maximum at the operating temperature of 300 degrees C. The gas response of the Zr-added CaFe2O4-based sensor at 300 degrees C was estimated to be 2.5 times higher than that of the sensor made from pure CaFe2O4 powder. However, the 90% response time of the Zr-added CaFe2O4-based sensor was much quicker at 350 degrees C than that at 300 degrees C. Thus, the optimal gas sensing performance of the Zr-added CaFe2O4-based sensor is expected to be obtained at the operating temperature of 350 degrees C, considering the still higher response to CO2 gas at this temperature. It is noted that the present CaFe2O4-based sensor responded reversibly as well as continuously to CO2 gas. Infrared analysis revealed that the sensing mechanism of the present CaFe2O4-based sensor is the change in the electric resistance of CaFe2O4 caused by reactive CO2 adsorption with negatively charged oxide ions (O-) resulting in the increase in the hole concentration in the base material of CaFe2O4.

    DOI: 10.18494/SAM.2016.1277

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  • First-principles energy band calculation of Ruddlesden-Popper compound Sr3Sn2O7 using modified Becke-Johnson exchange potential 査読 国際誌

    Journal of Solid State Chemistry   232   163 - 168   2015年12月   ISSN:0022-4596

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jssc.2015.09.032

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  • Synthesis and X-ray crystallography of bipyrroles: impacts of a CO-pi interaction on their structure 査読 国際誌

    Tetrahedron Letters   56 ( 11 )   1407 - 1410   2015年3月   ISSN:0040-4039

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.tetlet.2015.01.159

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  • Molecular orbital calculations of Eu-doped SrAl2O4 clusters 査読 国際誌

    Solid State Communications   206   42 - 45   2015年3月   ISSN:0038-1098 eISSN:1879-2766

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The electronic structures of uncloped and Eu2+-doped SrAl2O4 clusters are evaluated from the relativistic molecular orbital (RMO) calculation. The calculated forbidden gaps between the highest and lowest unoccupied molecular orbitals of [SrAl2O21](22-) and [SrAl12O38](34-) clusters are calculated to be 83 and 7.3 eV, respectively. When a Eu atom replaces a Sr atom, the Eu 4f states appear in the forbidden gap of the SrAl2O4 and the Eu 5d states are distributed widely in the conduction band. Combining the RMO calculation and the configuration interaction method for [EuO7](12-) and [EuO8](14-) clusters produces three or two theoretical peaks respectively for the transition 4f(7) -> 4f(6) 5d(1) in Eu2+-doped SrAl2O4, respectively. (C) 2015 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.ssc.2015.01.013

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  • Formation of CaFe<sub>2</sub>O<sub>4</sub> porous structure by addition of Zr in malic acid complex 査読 国際誌

    OBUKURO Yuki, OBATA Kenji, MAEDA Ryosuke, MATSUSHIMA Shigenori, OKUYAMA Yuji, MATSUNAGA Naoki, SAKAI Go

    Journal of the Ceramic Society of Japan   123 ( 1442 )   995 - 998   2015年   ISSN:1882-0743

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:公益社団法人 日本セラミックス協会  

    The effect of Zr addition into malic acid complex was examined for the purpose of the improvement of microstructure and specific surface area of CaFe<sub>2</sub>O<sub>4</sub>. The CaFe<sub>2</sub>O<sub>4</sub> phase could be obtained for both unadded and Zr-added (5 and 10 mol % with respect to Fe) system by calcination of precursor derived from malic acid complex at 700&deg;C which is almost 200&deg;C lower than that of conventional solid-state reaction method. Among the examined products, only the 5 mol % Zr-added product revealed characteristic smaller grains connected three dimensional porous structures resulting in higher specific surface area compared with unadded and 10 mol % Zr-added products. XPS measurements revealed that there are no notable changes in valence state for all constituent elements. The obtained final product of 5 mol % Zr-added CaFe<sub>2</sub>O<sub>4</sub> is worth further investigate for various application from a view point of improved higher specific surface area and characteristic microstructure as well as the functionality of the material itself.

    DOI: 10.2109/jcersj2.123.995

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  • Preparation and Characterization of Heterobimetallic Complex, Sr[Bi(DTPA)]&middot;9H<sub>2</sub>O, Derived La-Doped Sr<sub>2</sub>Bi<sub>2</sub>O<sub>5</sub> 査読 国際誌

    Obukuro Yuki, Sakai Go, Okuyama Yuji, Matsunaga Naoki, Matsushima Shigenori, Obata Kenji, Asato Eiji

    Chemistry Letters   44 ( 7 )   890 - 892   2015年   ISSN:0366-7022

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:公益社団法人 日本化学会  

    Single-phase Sr<sub>2</sub>Bi<sub>2</sub>O<sub>5</sub> was formed by calcination of the heterobimetallic complex, Sr[Bi(DTPA)]&middot;9H<sub>2</sub>O, at 700 &deg;C for 6 h in air. La-doping by 5 and 10 mol % into Sr<sub>2</sub>Bi<sub>2</sub>O<sub>5</sub> was also examined. There were no traces of impurity phase in the 5 mol % La-doped Sr<sub>2</sub>Bi<sub>2</sub>O<sub>5</sub> powder, on the other hand, impurity phases such as Sr<sub>3</sub>Bi<sub>4</sub>O<sub>9</sub> and SrCO<sub>3</sub> were identified for the 10 mol % La-doped sample. UV&ndash;vis spectroscopy revealed that the absorption edge of La-doped Sr<sub>2</sub>Bi<sub>2</sub>O<sub>5</sub> exhibits red shift as compared to the pure Sr<sub>2</sub>Bi<sub>2</sub>O<sub>5</sub> and the shift increases with the increase of La<sup>3+</sup> doping. It was confirmed that the photocatalytic activity of Sr<sub>2</sub>Bi<sub>2</sub>O<sub>5</sub> for the oxidation of isopropanol is improved with La doping under visible-light irradiation (&lambda; &ge; 420 nm).

    DOI: 10.1246/cl.150178

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  • Preparation of magnesium ferrite by a malic acid complex 査読 国際誌

    Journal of the Ceramic Society of Japan   122   645 - 648   2014年8月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    Nanopowder of MgFe2O4 was prepared from an organic acid complex method. Among three kinds of organic acids examined, it was found from an XRD measurement that the highest purity powder of MgFe2O4 was obtained from a malic acid complex. SEM observation revealed that the powder is fluffy aggregates and each particle has irregular shape. The TG-DTA and IR measurements show that thermolysis process of a malic acid complex in air was mainly constructed at two stages consisting of dehydration and ligand pyrolysis. Furthermore, it was confirmed from a VSM measurement that the saturation magnetization of MgFe2O4 nanopowder is much smaller value than that of the bulk material. (C) 2014 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.122.645

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  • Fabrication of p-i-n devices consisting of ZnO quantum dots embedded in Ga2ZnO4 film 査読 国際誌

    Japanese Journal of Applied Physics   53 ( 6 )   06JG09-1 - 06JG09-5   2014年6月   ISSN:0021-4922 eISSN:1347-4065

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

    ZnO films have been prepared at substrate temperatures of 125 to 200 degrees C by chemical vapor deposition with a precursor of Zn4O(CH3COO) 6. As the substrate temperature decreases, the grain size of ZnO crystals decreases. From transmission electron microscopic observations, the film grown at 125 degrees C is found to be constructed from ZnO quantum dots with a diameter of ca. 5 nm. Ultraviolet emissions are seen at 367, 375, 380, and 384nm in photoluminescence spectra of the ZnO films grown at 125, 150, 175, and 200 degrees C, respectively. The blue shift of the ultraviolet emissions is ascribed to the quantum confinement effect. After the deposition of a Ga2ZnO4 film with a thickness of 20 nm on the ZnO QD film grown at 125 degrees C, a visible emission disappears and the ultraviolet emission intensity significantly increases. Such an increase is due to the partial embedding of ZnO QDs in Ga2ZnO4 films. The insertion of the ZnO QD films in the p-i-n devices constructed from In1.8Zn0.2O3/InGaZnO4/ Ga2ZnO4/Ni0.7Zn0.3O/Ni does not improve their rectification properties, and electroluminescence is not observed in these devices at forward voltages of 10V or more. (C) 2014 The Japan Society of Applied Physics

    DOI: 10.7567/JJAP.53.06JG09

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  • Electronic structure of Eu2+-doped SrAl2O4 using modified Becke–Johnson exchange potential 査読 国際誌

    Solid State Communications   186   46 - 49   2014年5月   ISSN:0038-1098 eISSN:1879-2766

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The optimized electronic structure of Eu2+-doped SrAl2O4 is calculated by using the modified Becke-Johnson potential combined with the local density approximation. The calculated minimum energy gap of SrAl2O4 is 6.9 eV, which is close to the experimental value (similar to 6.5 eV). When a Eu atom replaces one of the Sr atoms, Eu 4f majority-spin states appear in the forbidden gap of SrAl2O4, which is estimated to be 5.5 eV above the valence band maximum. Considering spin-orbit coupling, Eu 4f majority-spin states decompose into two energy states and Eu 4f minority-spin states also appear in the band gap of SrAl2O4. (C) 2014 Elsevier Ltd. All rights reserved,

    DOI: 10.1016/j.ssc.2014.01.026

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  • Improved calculation of band gap of Sr2Bi2O5 crystal using modified Becke–Johnson exchange potential 査読 国際誌

    Journal of Physics and Chemistry of Solids   75 ( 3 )   427 - 432   2014年3月   ISSN:0022-3697 eISSN:1879-2553

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The electronic structure of Sr2Bi2O5 is calculated by the scalar-relativistic full potential linearized augmented plane wave (FLAPW+lo) method using the modified Becke-Johnson potential combined with the local density approximation correlation (MBJ-LDA). Both the valence band maximum (VBM) and conduction band minimum (CBM) exist at the F-point, indicating that Sr2Bi2O5 is a direct-band-gap material. The band gap is calculated to be 3.17 eV, which is very close to the experimental value. This result is in great contrast to the underestimation based on the GGA calculation. On the other hand, there is only a small difference in the effective masses of holes and electrons photogenerated near the VBM and CBM for the MBJ-LDA and GGA approaches. The optical properties of Sr2Bi2O5 are calculated from the complex dielectric function epsilon(omega)=epsilon(1)(omega)+i epsilon(2)(omega). A highly polarized peak is observed at 3.5 eV in the epsilon(2)(omega) function. Furthermore, the absorption coefficient estimated from the MBJ-LDA is very similar to that from the experimental result. (C) 2013 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.jpcs.2013.11.015

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  • Characterization of Ti-doped CaFe2O4 prepared from a malic acid complex 査読 国際誌

    Journal of the Ceramic Society of Japan   122   175 - 178   2014年2月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    Ti-doped and undoped CaFe2O4 powders were prepared from a malic acid complex and their properties were evaluated using analytical instruments. According to an XRD measurement, there were no traces of impurity phases in 5 mol % Ti-doped CaFe2O4 powder, while impurity phases such as alpha-Fe2O3 and CaTiO3 were observed for 10 mol % Ti-doped CaFe2O4. When Ti was added to CaFe2O4, the crystallite growth of CaFe2O4 was suppressed and the BET surface area increased. SEM observation revealed that the addition of Ti atoms to CaFe2O4 causes interconnected CaFe2O4 particles to separate. From the results of an XRF measurement, it is suggested that Fe atoms are substituted with Ti atoms. The optical band gap of CaFe2O4 hardly changed as a result of doping with Ti. (C) 2014 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.122.175

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  • Electronic structure of CaFe2O4 with antiferromagnetic spin ordering 査読 国際誌

    Journal of the Ceramic Society of Japan   121   766 - 769   2013年9月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    The electronic structure of antiferromagnetic CaFe2O4 is calculated by using a generalized gradient approximation considering on-site Coulomb interaction between d-electrons (GGA+U). We found that the antiferromagnetic phase is the most stable among non-magnetic, ferromagnetic, and antiferromagnetic phases. With GGA+U, the band gap energy of CaFe2O4 is calculated to be ca. 1.9 eV. The lower conduction band consists of the Fe 3d states split into t(2g) and e(g) states by the octahedral FeO6 environment. The Ca 3d states distribute upper conduction bands. On the other hand, the valence band is mainly composed of the interaction between Fe 3d and O 2p states. The valence band maximum is approximately located at the Z-point and the conduction band minimum at the X-point. This means that antiferromagnetic CaFe2O4 is an indirect energy gap material. The absolute value of the magnetic moment at Fe sites is calculated to be 4.16 mu(B), which is very close to experimental values. (C)2013 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.121.766

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  • First-principles study on electronic structure and optical properties of Ca 4Bi 6O 13 crystal 査読 国際誌

    Journal of Physics and Chemistry of Solids   74 ( 1 )   25 - 29   2013年1月   ISSN:0022-3697

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    The electronic structure of Ca 4Bi 6O 13 is calculated by the GGA approach. The valence band maximum and the conduction band minimum of Ca 4Bi 6O 13 are located at Γ-point. This means that Ca 4Bi 6O 13 is a direct band gap material. The conduction band in the lower energy region is mainly constructed with the admixture of Bi 6p and O 2p. The conduction band in the higher energy region consists of Ca 3d states. The valence band in the lower energy region is mainly formed from Bi 6s states, and the valence band in the upper energy region consists of O 2p states hybridizing with Bi 6s and 6p states. The optical properties of Ca 4Bi 6O 13 are calculated from spectral dependence of the complex dielectric function, ε(ω)=ε 1(ω)iε 2(ω). A highly polarized peak is observed below 3.6 eV in ε 2(ω) function. © 2012 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.jpcs.2012.07.012

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  • p-type ZnO films prepared by alternate deposition of ZnO and Mg 3N 2 films 査読 国際誌

    Journal of Physics and Chemistry of Solids   74 ( 1 )   80 - 85   2013年1月   ISSN:0022-3697

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    A p-type ZnO film was successfully obtained by the alternate deposition of ZnO and Mg 3N 2 in radio-frequency (RF) magnetron sputtering process. ZnO and Mg 3N 2 (or Mg-oxynitride) films were alternately deposited on a substrate rotated above ZnO and Mg 3N 2 targets, where ZnO and Mg 3N 2-sputtering were carried out at RF power of 30 W and 0-90 W, respectively. In the case of the alternate deposition, where the substrate was kept for 0.2 s above the Mg 3N 2 target, p-type ZnO films were grown by Mg 3N 2-sputtering at 50-70 W, whereas an n-type ZnO film was grown at 90 W. The c-axis lengths of the films prepared by Mg 3N 2-sputtering at 0-50 W increase with RF power, and oppositely the c-axis lengths of the films prepared by Mg 3N 2-sputtering at 60-90 W decrease with RF power. p-type ZnO films were grown by Mg 3N 2-sputtering at 50 W for 2 and 5 s, whereas insulative ZnO films were grown by Mg 3N 2-sputtering at 70 W for 2 and 5 s. The band-gap energies of the p-type ZnO films prepared by Mg 3N 2-sputtering at 50 W for 0.2 and 5 s are estimated to be 3.31 and 3.39 eV, respectively. The increase of the band-gap energies of the p-type ZnO films is caused by the intermixing of ZnO and Mg-oxynitride films. © 2012 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.jpcs.2012.08.003

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  • Preparation of visible-light-active photocatalysts having Cu-contained layer by plasma CVD 査読 国際誌

    Nanoscience and Nanotechnology Letters   4   581 - 584   2012年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1166/nnl.2012.1370

  • Preparation of p-type ZnO films by alternate deposition of ZnO and Mg3N2 films 査読 国際誌

    Procedia Engineering   36   427 - 433   2012年   ISSN:1877-7058

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:ELSEVIER SCIENCE BV  

    Films were deposited on a glass substrates heated at 100 degrees C by alternate deposition of ZnO and Mg3N2 films in an atmosphere of N-2 + 0.2% O-2. p-type ZnO films with the resistivity of 9.9x10(3) - 4.5x10(3) Omega cm were grown by Mg3N2 sputtering for 0.2 s at 50-70 W, whereas an n-type ZnO film was grown for 0.2 s at 90 W. Appearance of the n-type ZnO film is caused by a decrease of O-2-partial pressure in an atmosphere. The contraction of the c-axis due to the incorporation of Mg atoms is found in these p-type and n-type ZnO films. When the Mg3N2-depostion period was extended to 5s, p-type ZnO films were grown in the alternate sputtering at 50 W, whereas only insulator films were grown in the alternate sputtering at 70 W. The optical band gap of the films increases with both a RF power and a period of Mg3N2-deposition. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of MRS-Taiwan

    DOI: 10.1016/j.proeng.2012.03.062

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  • Visible light activity of photocatalytic composites composed of metal oxides 査読 国際誌

    Nanoscience and Nanotechnology Letters   4   712 - 715   2012年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1166/nnl.2012.1378

  • First-principles study on electronic structure of Sr2Bi2O5 crystal 査読 国際誌

    Journal of Physics and Chemistry of Solids   72 ( 12 )   1477 - 1481   2011年12月   ISSN:0022-3697

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The electronic structure of Sr(2)Bi(2)O5 is calculated by the GGA approach. Both of the valence band maximum and the conduction band minimum are located at Gamma-point. This means that Sr2Bi2O5 is a direct band-gap material. The wide energy-band dispersions near the valence band maximum and the conduction band minimum predict that holes and electrons generated by band gap excitation have a high mobility. The conduction band is composed of Bi 6p, Sr 4d and O 2p energy states. On the other hand, the valence band can be divided into two energy regions ranging from -9.5 to -7.9 eV (lower valence band) and from -4.13 to 0 eV (upper valence band). The former mainly consists of Bi 6s states hybridizing with O 2s and O 2p states, and the latter is mainly constructed from O 2p states strongly interacting with Bi 6s and Bi 6p states. (C) 2011 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.jpcs.2011.08.030

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  • Preparation and characterization of Ca4Bi6O13 complex oxide 査読 国際誌

    Chemistry Letters   40 ( 3 )   288 - 289   2011年3月   ISSN:0366-7022 eISSN:1348-0715

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    A single phase of Ca4Bi6O13 crystal was obtained at lower calcination temperature in a citric acid complex method than in a solid-state reaction. From the diffuse reflection spectra, it was found that Ca4Bi6O13 is direct-gap material and that the optical band gap is 2.92 eV. After heating at 600 degrees C or above, the specific surface area of Ca4Bi6O13 powder was ca. three times larger when prepared by a citric acid complex method than by solid-state reaction. Further, it was confirmed that the photocatalytic activity of Ca4Bi6O13 for the degradation of Methylene Blue (MB) was higher in a citric acid complex method than in a solid-state reaction under visible-light irradiation (lambda &gt;= 420 nm).

    DOI: 10.1246/cl.2011.288

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  • Possibility for hole doping into amorphous InGaZnO4 films prepared by RF sputtering 査読 国際誌

    Physica Status Solidi C   8 ( 2 )   531 - 533   2011年   ISSN:1862-6351

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:WILEY-V C H VERLAG GMBH  

    Amorphous InGaZnO4 (IGZO) films codoped with Al and N atoms were prepared by sputtering of targets consisting of IGZO and AlN powders in Ar + O-2 atmospheres. No hole-conductivity is seen in films deposited at 2x10(-3) Torr, whereas hole-conductivity is found in films deposited at 2x10(-2) Torr at radio frequency powers of 60-80 W in 0.3-0.6% O-2 atmospheres. The amorphous p-type IGZO film has the resistivity of 210 Omega cm, hole-density of 7.5x10(17) cm(-3), and mobility of 0.4 cm(2)/Vs. The rectification characteristic is obtained for a device constructed from Au, amorphous p-type IGZO, and amorphous n-type IGZO. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

    DOI: 10.1002/pssc.201000442

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  • First-principles energy band calculation for CaBi2O4 with monoclinic structure 査読 国際誌

    Hiroyuki Nakamura, Shin&apos, ichirou Ishii, Kenji Yamada, Shigenori Matsushima, Masao Arai, Kenkichiro Kobayashi

    Materials Chemistry and Physics   139 ( 1-2 )   385 - 389   2010年5月   ISSN:0254-0584

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    The electronic structure of CaBi2O4 is calculated by a GGA approach. The valence band maximum is approximately located at the Gamma-point or the Y-point and the conduction band minimum at the V-point. This means that CaBi2O4 is an indirect energy gap material. The conduction band is composed of Bi 6p-O 2p interaction. On the other hand, the valence band can be divided into two energy regions ranging from -9.92 to -7.40 eV (lower valence band) and -4.69 to 0 eV (upper valence band). The former is mainly constructed from Bi 6s states interacting slightly with O 2s and 2p states, and the latter consists of 0 2p states hybridizing with Bi 6s and 6p states. The states near the valence band maximum are strongly localized and the mobility of holes generated by band gap excitation is predicted to be fairly low. (C) 2010 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.matchemphys.2010.01.057

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  • CO2 sensing performances of potentiometric sensor based on Na1+xZr2Si2PO12 (0<x<3) 査読 国際誌

    Journal of the Ceramic Society of Japan   118 ( 1375 )   213 - 216   2010年3月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    Potentiometric CO2 sensors based oil NASICON (Na1+xZr2Si2PO12) were fabricated by combining with a Li2CO3-BaCO3 (1:2 in molar ratio) auxiliary phase. The CO2 sensing properties of NASICON (x = 0, 1, 2, 2.75) sensors were investigated under dry condition at 450 degrees C. The electromotive force (EMF) values of NASICON sensors were proportional to the logarithm of CO, concentrations in the range of 250 to 2500 ppm. When exposed to dry air containing 250 ppm CO2, the EMF values of each sensor continuously changed toward a negative potential. From a X-Ray Diffraction (XRD) measurement, it was confirmed that new crystal phases such as Li2ZrO3, ZrO2, Na2Zr(PO4)(2) and Na5Zr(PO4)(3) were formed at the interface between sensing electrode and solid-state electrolyte, because of reaction between Li2CO3 and NASICON. The result of XRD measurement I In suggested that the base-EMF change closely related with the decrease of Li+ activity in auxiliary phase and Na2O activity NASICON. (C)2010 The Ceramic Society of Japan. All rights reserved.

    DOI: 10.2109/jcersj2.118.213

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  • Plasma CVD treatment for titanium dioxides to approach the high performance of photocatalysts by visible light irradiation 査読 国際誌

    Kazuya Yamamoto, Yuki Matsuura, Ayako Nakamura, Tatsuhiko Sonoda, Shigenori Matsushima, Kenji Yamada

    TENCON 2010: 2010 IEEE REGION 10 CONFERENCE   2228 - 2232   2010年   ISSN:0886-1420

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:IEEE  

    TiO(2) particles or casted thin films are treated with plasma CVD using the mixture of tantalum alkoxide and nitrogen gas or copper(II) acetylacetonate to improve the photocatalyst activities of TiO(2) irradiated by visible light. The layer formed on the surface of the TiO(2) after plasma treatment is composed of some species characterized by XPS measurement. The visible-light activity are shown after the plasma CVD treatment to the surface of TiO(2).

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  • Relationship between aging time and EMF change of potentiometric CO2 device using Na(1+x)Zr(2)Si(x)P(3-x)O(12) (0<x<3) 査読 国際誌

    Sensors and Actuators B-Chemical   139 ( 2 )   435 - 439   2009年6月   ISSN:0925-4005

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    Four kinds of NASICON (Na(1+x)Zr(2)Si(x)P(3-x)O(12), x =1, 1.5, 2 or 2.75)-based CO(2) devices were combined with a Li(2)CO(3)-BaCO(3) (1:2 in molar ratio) auxiliary phase to investigate their CO(2) sensing properties. The EMF values of NASICON devices were correlated linearly with the logarithm of CO(2) concentrations in the range of 250-2500 ppm at 450 degrees C. When exposed to 250 ppm CO(2) for 200 h under dry condition, the EMF of each NASICON device decreased with aging time. To research the cause of the EMF drift, a mixture that consists of NASICON and Li(2)CO(3) was heated at 750 degrees C in air. From X-ray diffraction measurement, it was confirmed that alkali-rich crystal phases such as Li(2)ZrO(3) and Na(5)Zr(PO(4))(3) were formed instead of Na(3)Zr(2)Si(2)PO(12) phase. This Suggests that the EMF drift relates with the formation of alkali-rich crystal phase at the interface between NASICON and auxiliary phase. (C) 2009 Published by Elsevier B.V.

    DOI: 10.1016/j.snb.2009.03.040

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  • CO(2) Sensing Performances of Potentiometric Sensor Based on Na(1+x)Zr(2)Si(2)PO(12) (0<x<3) 査読 国際誌

    Journal of the Ceramic Society of Japan   118   213 - 216   2009年   ISSN:0094-243X

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER INST PHYSICS  

    CO(2) sensing characteristics were investigated under dry condition for potentiometric CO(2) sensors: air, Au vertical bar NASICON (Na(1+x)Zr(2)Si(2)PO(12), x=0, 1, 2, 2.75) vertical bar Li(2)CO(3)-BaCO(3), Au, air + CO(2). The electromotive force (EMF) values of each NASICON sensor were linearly increased to the logarithm Of CO(2) concentrations in the range of 250 to 2500 ppm at 450 degrees C. EMF values of each sensor continue to change toward negative potential during the operation exposing to 250 ppm CO(2) under dry condition. For the sensor using NASICON (Na(3.75)Zr(2)Si(2)PO(12)) with rich Na component, base-EMF (EMF value to fix a 250 ppm CO(2)) could become fairly stable. In addition, from the use of a x-ray diffraction (XRD) measurements, the factor of EMF drifts caused the decrease of Na(2)O activity in NASICON by decomposition of NASICON components.

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  • Effect of thermal treatment on photocatalytic activity of N-doped TiO2 particles under visible light 査読 国際誌

    Thin Solid Films   516 ( 21 )   7482 - 7487   2008年9月   ISSN:0040-6090

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    Nitrogen-doped (N-doped) TiO2 particles are prepared by plasma treatment using nitrogen gas and thermal stability of visible light activity in the N-doped TiO2 particles is investigated. The particles are heat treated in either nitrogen or air atmospheres in the range of 373 to 673 K. Photocatalytic activity under visible light irradiation in the N-doped TiO2 particles decreases with increasing heat treatment temperature both in nitrogen and air atmospheres and is almost nonexistent at 673 K. Visible light absorption is conspicuous in the N-doped TiO2 particles after heat treatment in nitrogen atmosphere. Doped nitrogen atoms are removed from the particles by the heat treatment to form oxygen vacancies which cause visible light absorption. On the other hand, visible light absorption decreases with heat treatment in air. The doped nitrogen atoms are substituted with oxygen atoms during heat treatment such that the structure reverts to that of the original TiO2 particles. (C) 2008 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.tsf.2008.03.041

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  • Photocatalytic activity of TiO2 thin films doped with nitrogen using a cathodic magnetron plasma treatment 査読 国際誌

    Kenji Yamada, Hirokazu Yamane, Shigenori Matsushima, Hiroyuki Nakamura, Tatsuhiko

    Thin Solid Films   516 ( 21 )   7560 - 7564   2008年9月   ISSN:0040-6090

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    TiO2 films are treated using a magnetron nitrogen-plasma apparatus that can generate high density plasma to realize nitrogen-doping. The films are treated for 5 min with nitrogen plasma at a discharge power from 30 to 100 W by a radio frequency generator operating at 13.56 MHz. The plasma treated films show visible light absorption in the range of around 400-500 nm. light absorption above approximately 500 nm is also observed in the film plasma treated at a high discharge power. It is confirmed from N-1s and Ti-2p X-ray photoelectron spectra of the films that Ti-N bonds and oxygen vacancies are formed. Visible light activity of photocatalysis in the film increases with increasing discharge power and then decreases. Such an increase and decrease in the visible light activity are due to the formation of Ti-N bonds and oxygen vacancies, respectively. The visible light activity is improved with the optimum plasma treatment. (C) 2008 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.tsf.2008.05.048

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  • Low wet etching rates of ZnO films prepared by sputtering of mixed ZnO and AlN powder targets 査読 国際誌

    Thin Solid Films   516 ( 15 )   4894 - 4898   2008年6月   ISSN:0040-6090

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    ZnO films codoped with Al and N have been prepared by radio frequency magnetron sputtering in an Ar atmosphere, using targets of mixtures of ZnO and AlN powders. The Al-doped ZnO films are transparent, whereas the films codoped with Al and N are colored. The Al and N-concentrations in the colored films are estimated to be 4-7 at.% and 1-2 at.%, respectively. No enhancement of the carrier density is seen in the colored ZnO films, whereas the colored films exhibit lower etching rates of 3-5 nm/s in a 0.1 M HCl solution, in comparison with the Al-doped ZnO films. For the colored film, the anisotropic grain growth occurs, and cubic grains are produced after etching. The low etching rates of the colored films are ascribed to the epitaxial growth of AlN films on the surfaces of ZnO grains, rather than the incorporation of Al-N and Al-O bonds into the ZnO lattice. (C) 2007 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.tsf.2007.09.021

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  • Electronic structure of Bi2CuO4 with antiferromagnetic spin ordering 査読 国際誌

    Journal of the Ceramic Society of Japan   116 ( 1352 )   589 - 592   2008年4月   ISSN:1882-0743 eISSN:1348-6535

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    The electronic structure of antiferromagnetic Bi2CuO4 is calculated by using generalized gradient approximation considering on-site Coulomb interaction between d-electrons (GGA+U). The GGA+U calculation indicates clearly that the antiferromagnetic phase is the stablest among non-magnetic, ferromagnetic and antiferromagnetic phases. By using U parameter (7.48 eV) and J parameter (0.95 eV), the band gap energy of Bi2CuO4 is calculated to be ca. 2.4 eV, which is comparable to the experimental one. The valence band maximum is approximately located at the X-point and the conduction band minimum at the Gamma-point. This means that antiferromagnetic Bi2CuO4 is an indirect energy gap material. The calculated total density of states of Bi2CuO4 Well corresponds to the state density experimentally deduced by x-ray photoelectron and electron-energy-loss spectroscopy. Also, it is found from the partial density of states analysis that the top of the valence band is mainly formed by O 2p orbitals, whereas the lower conduction band mainly consists of Cu 3d(x)(2)-(2)(y) orbitals. The magnetic moment at Cu sites is calculated to be 0.72 mu(B), which is close to experimental values. (c) 2008 The Ceramic Society of Japan. All rights reserved.

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  • First-principles Energy Band Calculation of Bi2CuO4 with Antiferromagnetic Structure 査読 国際誌

    S. Matsushima e, al. (co

    Journal of the Ceramic Society of Japan   116 ( 1352 )   589 - 592   2008年4月   ISSN:1348-6535

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.2109/jcersj2.116.589

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  • NASICON-based NO2 device attached with metal oxide and nitrite compound for the low temperature operation 査読 国際誌

    Kenji Obata, Shigenori Matsushima

    Sensors and Actuators B   130 ( 1 )   269 - 276   2008年3月   ISSN:0925-4005

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    NASICON (Na3Zr2Si2PO12)-based potentiometric NO2 devices, such as Au-attached, (ITO, NaNO2)-attached and (ITO, NaNO2-Li2CO3)-attached types, were fabricated and their NO2 sensing properties were investigated in the range of 2-7 ppm NO2 under 1-50% relative humidity (RH) between 30 degrees C and 150 degrees C. The Au-attached device had a NO2 sensing capability under wet condition (30% RH) without an auxiliary phase, although it showed no EMF response under dry condition (below 1% RH). This result suggests that NO2 sensing reaction of the device is closely related with water vapor. To enlarge the NO2 sensitivity at room temperature, a (metal, nitrite)-attached device was fabricated by combining ITO with NaNO2. The EMF change of the (ITO, NaNO2)-attached device was estimated to be 43.6 mV under 30% RH in the range of 2-7 ppm NO2 and enlarged remarkably in comparison with 17.7 mV of the Au-attached device. However, the NO2 sensitivity of the (ITO, NaNO2)-attached device was riot only fluctuated by the change of relative humidity, but the EMF values shifted upward with increasing humidity at a fixed NO2 concentration. It is considered that this originates from the fact that a nitrite auxiliary phase is easy to dissolve in water. Therefore, Li2CO3 with durability to water vapor was melted together with NaNO2 and used as the auxiliary phase of the (ITO, NaNO2)-attached device. As the result, it was found that the EMF change of the (ITO, NaNO2-Li2CO3)-attached device was constant almost without depending on humidity. The EMF values of the device were also proportional to the logarithm of NO2 concentration and well consistent with theoretical values obtained from the Nernstian equation. (C) 2007 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.snb.2007.07.142

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  • Electrical and optical properties of ZnO films prepared by sputtering of ZnO targets containing AlN 査読 国際誌

    Applied Surface Science   253 ( 11 )   5035 - 5039   2007年3月   ISSN:0169-4332

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    ZnO films prepared from the ZnO target containing 2% AIN are transparent irrespective of radio frequency (RF) power. The obtained ZnO films have the carrier density of 3.8 x 10(20) cm(-3) or less and the low mobility of 5.3-7.8 cm(2)/(V s). In the case of 5% AIN target, ZnO films prepared at 40, 60 and 80 Ware transparent, whereas ZnO films prepared at 100 and 120 Ware colored. As RF power increases from 40 to 120 W, the carrier density increases straightforwardly up to 5.5 x 10(20) cm(-3) at 100 Wand is oppositely reduced to 3.2 x 10(20) cm(-3) at 120 W. In the case of 10% AIN target, ZnO films prepared at 60 W or more are colored, and have the carrier density of 4 x 10(20) cm(-3) or less. The N-concentration in these colored films is estimated to be 1% or less. The Al-concentration in the ZnO films prepared from the 5 and 10% AIN targets is higher than 2%. The carrier density of the ZnO films containing Al and N atoms is nearly equal to that of ZnO films doped with Al atoms alone. There is no evidence in supporting the enhancement of the carrier density via the formation of N-AlxZn4-x clusters (4 &gt;= x &gt;= 2). (c) 2006 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.apsusc.2006.11.019

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  • First-principles energy band calculation for undoped and S-doped TiO2 with anatase structure 査読 国際誌

    Shigenori Matsushima, Kenji Takehara, Hirokazu Yamane, Kenji Yamada, Hiroyuki Nakamura, Masao Arai, Kenkichiro Kobayashi

    Journal of Physics and Chemistry of Solids   68 ( 2 )   206 - 210   2007年2月   ISSN:0022-3697

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The electronic structure of S-doped TiO2 with an optimized anatase structure was calculated within the framework of the density functional theory (DFT). For the calculation we built four kinds of supercells; type-A and B supercells consist of 12 and 48 atoms and a centered Ti atom is substituted for an S atom, while type-C and D supercells consist of 12 and 48 atoms and a centered 0 atom is substituted for an S atom. The supercells (type-B and D) were employed to adjust the S-concentration in TiO2 to an experimental value of a few %. The changes of the lattice parameters are not significant in the type-A and B supercells. The phase transition from the tetragonal to the orthorhombic occurs in the type-C and D supercells. In the small supercell (type-A), S-related states are located in the range of -1.6 to 0 eV, and the S-states are band-like. In contrast, in the large supercell (type-B), S-related states appeared at about 0.9 eV above the top of the valence band, and the S-states are atomic-like. The localization of the S-related states is remarkable in the type-B supercell. In the type-D supercell, the S-related states were merged with the top of the valence band, and as a result the band-gap energy is narrowed by 0.7 eV. Despite a low S-concentration (3%) in the type-D supercell, the S-related states are somewhat band-like. (c) 2006 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/j.jpcs.2006.10.011

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  • Effect of plasma-polymerized layer formed on a surface of titanium dioxide particle on its photocatalytic activity 査読 国際誌

    Journal of the Vacuum Society of Japan   50 ( 10 )   629 - 634   2007年   ISSN:0559-8516

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Vacuum Society of Japan  

    If TiO2 particles are used as components of paint without any surface modification, binding resin of the paint will be easily decomposed by the photocatalytic activity of the particles. In this work, plasma polymerization of octamethylcyclotetrasiloxane as a siloxane monomer is tried to form thin layer stable to the photocatalytic activity on the surface of TiO2 particles. The plasma-polymerized layer containing Si-O and Si-C bonds is formed on the surface of the particles and shows stability to the photocatalytic activity of TiO2. The particles surface-modified with the plasma polymerization exhibit visiblelight activity. The visible-light activity is originated from carbon doping which brings about in the particles during the plasma polymerization, and is thermally stable to be maintained after annealing at 673 K.

    DOI: 10.3131/jvsj.50.629

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  • Effects of heat treatment and surface modification on photocatalytic property in TiO2 particles having plasma-polymerized surface layer 査読

    Kenji Yamada, Naoko Iwasawa, Tatsuhiko Sonoda, Hirokazu Yamane, Shigenori Matsushima, Hiroyuki Nakamura

    Polymer Preprints, Japan   55 ( 2 )   4350 - 4351   2006年

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    記述言語:日本語   掲載種別:研究論文(国際会議プロシーディングス)  

    Antiphotocatalytic and thin layer should be formed on the surface of TiO2 particles by plasma polymerization to depress photocatalytic decomposition of binding resin, when the particles are used as components of paint. The particles were plasma-polymerized with octamethylcyclotetrasiloxane as a monomer. The particles were doped with carbons to form Ti-C bonds during the plasma polymerization. The carbon-doped particles revealed visible-light absorption and methylene blue molecules adsorbed on the surface of the particles were decomposed with visible-light irradiation. Composition ratio of Si/Ti at the surface of the plasma- polymerized particles was a little decreased by heat-treating at 673 K in air. Infrared absorption associated with Si-CH 3 stretching vibration disappeared substantially to be similar to silica-like and silicon carbide-like structure after the heat treatment. The carbon-doping and the visible-light activity in the particles were almost maintained after the heat treatment.

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  • Photoluminescence spectra of ZnO films doped with Li and Cl atoms 査読 国際誌

    Key Engineering Materials   301   185 - 188   2006年   ISSN:1013-9826

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:TRANS TECH PUBLICATIONS LTD  

    ZnO films doped with Li and Cl atoms have been prepared by organometallic chemical vapor deposition method. In photoluminescence spectra of the doped ZnO films, strong emission appears at 376 nm which is slightly longer than that of free-excitons. As excitation intensity increases, a peak wavelength of the emission is shifted toward a shorter value. The emission near band-gap edge is assigned to radiative recombination via Li-Cl pairs.

    DOI: 10.4028/0-87849-982-2.185

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  • Sensing properties of NASICON-based NO2 sensor attached with metal oxide operative at room temperature 査読 国際誌

    Electrochemistry   73 ( 11 )   956 - 958   2005年11月   ISSN:1344-3542

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELECTROCHEMICAL SOC JAPAN  

    NASICON (Na3Zr2Si2PO12)-based potentiometric NO2 devices, such as an Au-attached and an (ITO, NaNO2)-attached types, were prepared and their NO2 sensing properties investigated in the range of 1.9 to 6.7 ppm NO2 diluted with air at 30 degrees C. The Au-attached device was found to have a NO2 sensing capability under a humidity condition (30% RH) without any auxiliary phase, although it showed no EMF response under a dry condition (below 1% RH). This experimental result suggests that NO2 sensing reaction of the device is closely related with water vapor. To enhance the NO2 sensitivity of the NASICON-based. device, the (ITO, NaNO2)-attached device was therefore fabricated. As the result, the AEMF of the (ITO, NaNO2)-attached device was estimated to be 43.6 mV under 30% RH in the range of 1.9 - 6.7 ppm NO2, and improved more remarkably in comparison with 17.7 mV of the Au-attached device.

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  • NASICON-based potentiometric CO2 sensor combined with new materials operative at room temperature 査読 国際誌

    Sensors and Actuators, B: Chemical   108 ( 1-2 )   352 - 358   2005年7月   ISSN:0925-4005

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    The improvement for the deterioration of CO2 sensing properties in lower humidity condition was attempted to a NASICON-based potentiometric CO2 device operative at room temperature. To optimize the sensing electrode, the device was fabricated by using ITO powders with a large specific surface area and by using a mixture of ITO and basic oxide powders. Although CO2 sensing properties of the device were markedly improved by applying the above ideas in lower humidity condition, it was confirmed that the basic EMF drifts with changing the humidity conditions. Further, to find out the appreciate reference electrode material, the thermal and chemical stabilities were examined by XRD measurement for three kinds of oxides such as Li 0.62CoO2, Na0.6CoO2 and Li 2TiO3. As the results, Na0.6CoO2 and Li2TiO3 were much stabler than Li0.62CoO 2 thermally and chemically. It was also found that Li 2TiO3 has a poor electric conductivity. Therefore, Na 0.6CoO2 is the most suitable material for the reference electrode of the NASICON-based device operative at room temperature. © 2005 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.snb.2004.12.119

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  • Photocatalytic property and electronic structure of triple-layered perovskite tantalates, MCa2Ta3O10 (M = Cs, Na, H, and C6H13NH3) 査読 国際誌

    Journal of Physical Chemistry B   109 ( 16 )   7801 - 7806   2005年4月   ISSN:1520-6106

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    The Dion-Jacobson series of triple-layered perovskite tantalates (MCa2Ta3O10, M = Cs, Na, H, and C6H13-NH3) were synthesized to evaluate their photocatalytic activity for overall water splitting to evolve H-2/O-2 under UV irradiation. The photocatalytic activity was susceptible to the hydration of interlayer space. The hydrous Na phase exhibited much higher activity (H-2: 308 mu mol(.)h(-1)) compared to the anhydrous Cs phase (24 mu mol(.)h(-1)) and the hydrous H phase (22 mu mol(.)h(-1)) in the presence of 0.5 wt % Ni impregnated. H2O/D2O isotopic experiment suggested that the hydrated interlayer plays as an active site for water splitting, where the high mobility of water molecule in the interlayer should correlate with the total photocatalytic activity. The FLAPW electronic structure calculation demonstrated that the terminating oxygen site, O(4), which faces to the interlayer space, contributes largely to the top of the valence band. Judging from comparison with the double-layered tantalates, MLaTa2O7, in our previous study, the contribution of terminating oxygen site to the band structure is supposed to depend on the number of perovskite layers.

    DOI: 10.1021/jp044833d

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  • Effect of titanium dioxide electrode nanostructure constructed by polymer organic-medium on photoelectric conversion efficiency for dye-sensitized solar cells 査読

    Hirokazu Yamane, Shun Shimosoyama, Keiko Masui, Shigenori Matsushima, Hiroyuki Nakamura, Kenji Yamada, Tisato Kajiyama

    Polymer Preprints, Japan   54 ( 1 )   1442   2005年

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    記述言語:日本語   掲載種別:研究論文(国際会議プロシーディングス)  

    Since Gratzel and coworkers developed a new type solar cell based on the nanocrystalline titanium dioxide (TiO2) electrode sensitized to visible light with dye molecules, which had a high overall energy conversion efficiency of 10%, the goal of efficient solar cells has focused on dye-sensitized photochemical solar cells. For the performance of the cell, the porous surface nanostructure of the TiO2 electrode is very important. In this paper, molecular weight, M.W. and weight fraction dependence of a polymer organic-medium on the nanostructure of TiO2 electrode and the photoelectrochemical performance of the dye-sensitized solar cell has been investigated. It has confirmed that polyethylene glycol (PEG) with high M.W. or 40wt% TiO2 fraction is a promising alternative polymer organic-medium leading to a higher open-circuit voltage
    short-circuit current density and a larger fill factor and thus a higher power output.

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  • Surface structure and photocatalytic property in plasma-polymerized TiO2 particles 査読

    Kenji Yamada, Kayo Ohira, Naoko Iwasawa, Hirokazu Yamane, Shigenori Matsushima, Hiroyuki Nakamura, Kiyoshi Kumada, Tisato Kajiyama

    Polymer Preprints, Japan   54 ( 1 )   1582   2005年

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

    When TiO2 particles are used as a component of paint without any surface modification, binding resin will be easily decomposed by photocatalytic property of the particles. In this work, it is tried that thin layer having silica-like structure is formed on the surface of TiO2 particles by plasma polymerization. The particles were pretreated with argon plasma and then were plasma-polymerized with octamethylcyclotetrasiloxane as a monomer. Thin layer composed of Si-O bonds was formed on the surface of the particles. Ratio of surface element, Si/Ti in the particles was increased with increasing plasma polymerization time. The particles surface-modified with the plasma polymerization revealed visible-light absorption and methylene blue molecules adsorbed on the surface of the particles were decomposed with visible-light irradiation. It is presumed that C doping or Si doping takes place in process of the plasma polymerization.

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  • Influence of titanium dioxide electrode nanostructure constructed by polymer organic-medium on photoelectric conversion efficiency for dye-sensitized solar cells 査読

    Hirokazu Yamane, Shun Shimosoyama, Keiko Masui, Shigenori Matsushima, Hiroyuki Nakamura, Kenji Yamada, Tisato Kajiyama

    Polymer Preprints, Japan   54 ( 2 )   4119   2005年

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    記述言語:日本語   掲載種別:研究論文(国際会議プロシーディングス)  

    Since Gratzel and coworkers developed a new type solar cell based on the nanocrystalline titanium dioxide (TiO2) electrode sensitized to visible light with dye molecules, which had a high overall energy conversion efficiency of 10%, the goal of efficient solar cells has focused on dye-sensitized photochemical solar cells. For the performance of the cell, the porous surface nanostructure of the TiO2 electrode is very important. In this paper, weight fraction and molecular weight, M.W. dependence of a polymer organic-medium on the nanostructure of TiO2 electrode and the photoelectrochemical performance of the dye-sensitized solar cell has been investigated. It has confirmed that polyethylene glycol (PEG) with 40wt% TiO2 fraction or high M.W. is a promising alternative polymer organic-medium leading to a higher open-circuit voltage
    short-circuit current density and a larger fill factor and thus a higher power output.

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  • First-principles band calculation of TiO2 with Brookite structure 査読

    S Matsushima, K Obata, H Yamane, K Yamada, H Nakamura, M Arai, K Kobayashi

    Electrochemistry   72 ( 10 )   694 - 696   2004年10月   ISSN:1344-3542

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELECTROCHEMICAL SOC JAPAN  

    The electronic structure of TiO2 with brookite structure is calculated within the framework of the density functional theory (DFT). Calculated lattice constants are in excellent agreement with experimental values. Brookite is predicted to be a material with a direct band gap at the F point. The valence band with the width ca. 4.8 eV is mainly constructed from O 2p orbitals, whereas the lower conduction band mainly Ti 3d orbitals.

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  • Fe Doping Effects on the Optical and Magnetic Properties of Indium Oxide 査読 国際誌

    S. Matsushima

    Transactions of the Materials Research Society of Japan   29   1509 - 1511   2004年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • First-principles energy band calculation for undoped and N-doped InTaO4 with layered wolframite-type structure 査読 国際誌

    S Matsushima, K Obata, H Nakamura, M Arai, K Kobayashi

    Journal of Physics and Chemistry of Solids   64 ( 12 )   2417 - 2421   2003年12月   ISSN:0022-3697

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    The electronic structures of undoped and N-doped InTaO4 with optimized structures are calculated within the framework of the density functional theory. Calculated lattice constants are in excellent agreement with experimental values, within a difference of 2%. The valence band maximum (VBM) is located near the middle point on the ZD line and the conduction band minimum (CBM) near the middle point on the DX line. This means that InTaO4 is an indirect-gap material and a minimum theoretical gap between VBM and CBM is ca. 3.7 eV. The valence band in the range from -6.0 to 0 eV mainly consists of 0 2p orbitals, where In 4d5s5p and Ta 5d orbitals are slightly hybridized with 0 2p orbitals. On the other hand, the conduction band below 5.5 eV is mainly composed of the Ta 5d orbitals and the contributions of In and 0 orbitals are small. The band gap of N-doped InTaO4 decreases by. 0.3 eV than that of undoped InTaO4, because new gap states originating from N 2p orbitals appear near the top of the valence band. This result indicates that doping of N atoms into metal oxides is a useful method to develop photocatalysts sensitive to visible light. (C) 2003 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/S0022-3697(03)00283-X

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  • Comparison of electronic structure of LiInO2 with NaInO2 査読 国際誌

    S Kawakami, M Sasaki, H Tabata, H Shimooka, S Kohiki, S Matsushima, M Oku, T Shishido

    JOURNAL OF ALLOYS AND COMPOUNDS   359 ( 1/2 )   278 - 280   2003年9月   ISSN:0925-8388

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    Electronic structure of NaCl type LiInO2 was compared experimentally and theoretically with that of alpha-NaFeO2 type NaInO2 to clarify the influences of Li-In direct interaction peculiar to LiInO2. Ultraviolet-visible diffuse reflectance spectrum of LiInO2, with the onset of absorption at 3.7 eV, was rather more simple than that of NaInO2 accompanied by two small peaks in the band gap of 3.7 eV. Discrete variational-Xalpha calculations for the [Li10In9O44](51-) and [Na7In12O44](45-) model clusters depicted well the features of absorption spectra of LiInO2 and alpha-NaInO2, respectively. The calculations also revealed that higher valence bands of LiInO2 and NaInO2 were dominated, respectively, by the Li 2s-In 5s bonding orbital with a large overlap population and the Na 3s,p-O 2p bonding orbital with a small overlap population, however, lower conduction bands in both LiInO2 and NaInO2 were formed by the In 5s-O 2p antibonding orbital. The experimental valence band spectrum of LiInO2, simply peaked at similar to4 eV below the valence band maximum, can be ascribed to overlapping of the Li 2s-In 5s bonding orbital with the In 5p-O 2p bonding orbital at around -3 eV in the density of states. (C) 2003 Elsevier B.V. All rights reserved.

    DOI: 10.1016/S0925-8388(03)00179-8

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  • Electronic structure of InTaO4 with monoclinic structure 査読 国際誌

    S Matsushima, H Nakamura, M Arai, K Kobayashi

    CHEMISTRY LETTERS   32 ( 1 )   64 - 65   2003年1月   ISSN:0366-7022 eISSN:1348-0715

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    担当区分:筆頭著者, 最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    From a first-principles band calculation, InTaO4 is predicted to be an indirect-gap material, because the valence band maximum (VBM) is located in the middle point on the ZD line and the conduction band minimum (CBM) in the middle point on the DX line. The valence band with the width ca. 6.0 eV is mainly constructed from O 2p orbitals hybridized with In4d5s5p and Ta5d orbitals, whereas the lower conduction band is constructed from Ta5d orbitals.

    DOI: 10.1246/cl.2003.64

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  • Photocatalytic properties of layered perovskite tantalates, MLnTa(2)O(7) (M = Cs, Rb, Na, and H; Ln = La, Pr, Nd, and Sm) 査読 国際誌

    M Machida, K Miyazaki, S Matsushima, M Arai

    JOURNAL OF MATERIALS CHEMISTRY   13 ( 6 )   1433 - 1437   2003年   ISSN:0959-9428

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    Layered lanthanide tantalates and their ion-exchanged phases (MLnTa(2)O(7), M = Cs, Rb, Na, and H; Ln = La, Pr, Nd, and Sm) were prepared to evaluate their photocatalytic activity for water splitting under UV irradiation. The optical band gap energy was dependent on the lanthanide, Ln, but negligibly affected by the monovalent interlayer cations, M. By contrast, the photocatalytic activity was strongly affected by not only Ln but also M; the highest activity was attained by a series of M = Rb with a sequence of Ln: Nd &gt; Sm &gt; La &gt; Pr. The effect of Ln can be explained by the energy level and hybridization of the Ln 4f band, which was discussed based on the results of electronic structure calculations in our previous work. The ion exchanged phases ( M = Na and H) having deformed hydrous layer structure were less active compared to anhydrous Rb and Cs phases, whereas the NiOx loading of the Na phase greatly enhances the activity. It seems that the high mobility of water molecules between the layers allows the interlayer sites to behave as active sites for the photocatalytic reaction over NiOx-loaded catalysts.

    DOI: 10.1039/b301938c

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  • First-principles energy band calculation for SrAl2O4 with monoclinic structure 査読 国際誌

    S Matsushima, H Nakamura, M Arai, CN Xu

    CHEMISTRY LETTERS   ( 7 )   700 - 701   2002年7月   ISSN:0366-7022 eISSN:1348-0715

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    担当区分:筆頭著者, 最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    The electronic structure of strontium aluminate, SrAl2O4, is calculated by using the scalar-relativistic full potential linearized augmented plane wave (FLAPW) method. SrAI(2)O(4) is predicted to be an indirect-gap material, since the valence band maximum locates near Z point and the conduction band minimum at F point. The valence band with the width ca. 5.3 eV is mainly constructed from 0 2p orbitals, where AI 3s3p and Sr 5s5p slightly hybridize with 0 2p, and the lower conduction band from Sr 5s orbitals.

    DOI: 10.1246/cl.2002.700

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  • Electronic structure of group III elements doped into ZnO by using molecular orbital calculation 査読 国際誌

    CHEMISTRY LETTERS   ( 6 )   580 - 581   2002年6月   ISSN:0366-7022 eISSN:1348-0715

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    The electronic structures of ZnO doped with group III elements (B, Al, Ga and In) are calculated by using the discrete variational Xalpha method of clusters. For ZnO doped with group III elements, new states originating from group III elements appear in the band gap. The depth energy of impurity-related states is the shallowest for Al and is the deepest for B.

    DOI: 10.1246/cl.2002.580

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  • First-principles energy band calculation for ZnSb2O6 with trirutile-type structure 査読 国際誌

    S Matsushima, T Tanizaki, H Nakamura, M Nonaka, M Arai

    CHEMISTRY LETTERS   ( 10 )   1010 - 1011   2001年10月   ISSN:0366-7022 eISSN:1348-0715

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    The electronic structure of ZnSb2O6 is calculated by using the FLAPW method and the DV-X alpha method. The valence band with the width of ca. 10.5 eV is roughly classified into the two bands, where O 2p orbitals are dominant and hybridize with Zn 3d and Sb 5s orbitals. On the other hand, the lower conduction band is mainly constructed from Sb 5s orbitals which have large spatial extent. Therefore, ZnSb2O6 crystal is expected to have large electron mobility with doping carriers.

    DOI: 10.1246/cl.2001.1010

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  • Effect of Mn doping on the electronic structure of ZnGa2O4 with spinel-type structure 査読 国際誌

    CHEMISTRY LETTERS   ( 7 )   664 - 665   2001年7月   ISSN:0366-7022 eISSN:1348-0715

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    The electronic structures of ZnGa2O4 and ZnGa2O4:Mn are calculated by the discrete variational X alpha method on model clusters. For ZnGa2O4, it is found that Zn-O and Ga-O bondings are not perfectly ionic but partially covalent. When a central Zn atom of the cluster is replaced with a Mn atom, the new energy states originating from Mn 3d orbitals appear in the energy gap. The energy levels of t(2) up-spin states and e down-spin states seem to relate to the green emission.

    DOI: 10.1246/cl.2001.664

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  • Preparation and characterization of lithium doped indium sesqui-oxide 査読 国際誌

    Masakuni Sasaki, Ryuta Kiyoshima, Shigemi Kohiki, Shigenori Matsushima, Masaoki Oku, Toetsu Shishido

    Journal of Alloys and Compounds   322 ( 1-2 )   220 - 225   2001年6月   ISSN:0925-8388

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Doping of lithium into indium sesqui-oxide (In2O3) brought about an increase in the lattice constant of cubic cell from 10.116 to 10.163 Å and a decrease in the optical absorption energy from 2.72 to 2.68 eV with increasing the nominal molar ratio x (=[Li]/[In2O3])&lt
    0.5. Enlargement of the lattice constant obeying the Vegard's law suggests that the doped Li atoms occupied interstitial sites of In2O3 crystal. Tight-binding (TB) band-structure calculations with two Li atoms at 8a sites and those at 16c sites of the crystal showed decrements in energy splitting between the valence and conduction bands by 0.2 and 0.1 eV, respectively, and supported the observed decrements of the optical absorption energy in In2O3:Lix. First-principles molecular-orbital (MO) calculations with clusters for Li atoms at 8a sites showed similar result to the TB calculation. Changes in the X-ray photoelectron valence band spectra of the In2O3:Lix (x=0, 0.2, and 0.5) agreed with those in the density of states expected from the TB and MO calculations. Non-linear current-voltage characteristics were due to the surface states and surface band bending observed in the valence band spectra. © 2001 Elsevier Science B.V.

    DOI: 10.1016/S0925-8388(01)01019-2

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  • Electronic Structure of Layered Tantalates Photocatalysts, RbLnTa2O7 (Ln = La, Pr, Nd, and Sm) 査読 国際誌

    S. Matsushima

    International Journal of Inorganic Materials   3 ( 6 )   545 - 550   2001年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Photocatalytic Properties and Electronic Structure of Lanthanide Tantalates, LnTaO4 (Ln = La, Ce, Pr, Nd and Sm). 国際誌

    S. Matsushima

    The Journal of Physical Chemistry B   105 ( 16 )   3289 - 3294   2001年5月   ISSN:1089-5647

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1021/jp004297z

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  • Difference of Electronic Structures between SrTiO3 and BaTiO3 査読 国際誌

    Journal of Ceramic Society of Japan   108 ( 1262 )   952 - 954   2000年10月   ISSN:1882-1022 eISSN:1348-6535

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    X-ray photoemission spectroscopy (XPS) measurements were performed on SrTiO3 and BaTiO3 single crystals with monochromated Al K alpha radiation. Valence band (VB) spectra of as-fractured SrTiO3 and BaTiO3 crystals exhibit two peaks arising from the O 2p pi and O 2p sigma bonding orbitals, From a partial density of states (PDOS) calculation, it is found that O 2p orbitals fairly hybridize with Ba 5p orbitals, while do not almost hybridize with atomic orbitals of Sr atom. This indicates that the nature of the chemical bonding of Ba-O in BaTiO3 is more covalent than that of Sr-O in SrTiO3.

    DOI: 10.2109/jcersj.108.1262_952

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  • Electronic Structure of ZnSb2O6 with Trirutile-Type Structure 査読 国際誌

    S. Matsushima

    Journal of the Mining and Materilas Processing Institute of Japan   116 ( 9 )   795 - 796   2000年9月   ISSN:0916-1740

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:The Mining and Materials Processing Institute of Japan  

    Electronic structure of ZnSb<sub>2</sub>O<sub>6</sub> was investigated using the discrete variational (DV)-Xα method on the model cluster [Zn<sub>5</sub>Sb<sub>10</sub>O<sub>56</sub>] <sup>52-</sup>. In the calculation, the band gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied MO (LUMO) was 3.80 eV. In the valence band, Sb-O and Zn-O bondings are considered to be not perfectly ionic but partially covalent because of the hybridization of O 2p orbitals with Sb 5sp and Zn 3d orbitals. Furthermore, ZnSb<sub>2</sub>O<sub>6</sub> crystal is expected to have a large electron mobility because Sb 5s orbitals are dominant at the bottom of the conduction band. The calculated net charges are +1.48e for Zn, -1.20e for O and +3.02e for Sb. The bond overlap populations are calculated to be 0.09 and 0.29 for Zn-O and Sb-O bondings, respectively. These results show that Sb-O bonding is more covalent than Zn-O bonding in ZnSb<sub>2</sub>O<sub>6</sub> crystal.<br>

    DOI: 10.2473/shigentosozai.116.795

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  • C3H6 Sensitive SmFeO3 Prepared from Thermal Decomposition of Heteronuclear Complexes, {Ln[Fe(CN)6]nH2O}x (Ln=La,Sm,Dy) 査読 国際誌

    松嶋 茂憲, 佐野 直美, 定岡 芳彦

    Journal of the Ceramic Society of Japan   108 ( 1259 )   681 - 682   2000年7月   ISSN:1882-1022

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:公益社団法人日本セラミックス協会  

    Perovskite-type LnFeO_3(Ln=La, Sm, Dy) powders were prepared by thermal decomposition of cyanidebridged heteronuclear complexes and their gas sensing properties to C_3H_6 were investigated. As a result, it was found that SmFeO_3 has the highest sensitivities to C_3H_6 among the perovskite oxides examined. By adding a small amount of Pd to SmFeO_3, gas-sensing properties such as gas sensitivity and response time were largely enhanced.

    DOI: 10.2109/jcersj.108.1259_681

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  • Molecular Orbital Calculation for BaTiS3 査読

    S. Matsushima

    Journal of the Mining and Materilas Processing Institute of Japan   116 ( 6 )   532 - 533   2000年6月   ISSN:0916-1740

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:The Mining and Materials Processing Institute of Japan  

    The electronic structure of BaTiS<sub>3</sub> was investigated using a discrete-variational Xα (DV-X α) method on the model cluster. In the calculation of [Ba<sub>6</sub>Ti<sub>3</sub>S<sub>48</sub>]<sup>72-</sup> cluster, the band gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) was 0.98 eV, which was much smaller than that of ionic crystal, BaTiO<sub>3</sub>. In the valence band region, S 3p orbitals hybridized with Ti 3d orbitals, while not with atomic orbitals of Ba atom. Net charges calculated for the [Ba<sub>6</sub>Ti<sub>3</sub>S<sub>48</sub>]<sup>72-</sup> cluster were + 1.911 for Ba, + 0.750 for Ti and -0.682 for S, respectively. Furthermore, the bond overlap population of Ti-S bond was very large, compared with the Ti-Ti and Ba-S bonds. These results indicate that the covalent interaction between Ti and S atoms plays a dominant role on chemical bond of BaTiS<sub>3</sub> crystal. <br>

    DOI: 10.2473/shigentosozai.116.532

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  • Molecular orbital calculation for N-doped ZnO 査読

    S Matsushima, K Kobayashi

    Electrochemistry   68 ( 6 )   537 - 539   2000年6月   ISSN:1344-3542

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELECTROCHEMICAL SOC JAPAN  

    The electronic structures of ZnO, Li-doped ZnO and N-doped ZnO are calculated using the discrete variational Xa: method on model clusters. For ZnO, it is found that the Zn-O bonding is not perfectly ionic but partially covalent because of the hybridization between Zn 3d and O 2p orbitals in the valence band. When a Zn atom of the cluster is replaced with a Li atom, the width of the valence band is expanded than that of the ZnO cluster, and at the same time the energy gap between HOMO and LUMO decreases. On the other hand, the new energy states originating from N 2p orbitals in the energy gap are formed for N-doped ZnO.

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  • Effect of La Doping on the Electronic Structure of SrTiO3 査読 国際誌

    S. Matsushima e, al. (co

    Journal Ceramic Society of Japan   108 ( 1257 )   518 - 520   2000年5月   ISSN:1882-1022 eISSN:1348-6535

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

    For undoped-SrTiO3 and La-doped SrTiO3 single crystals, X-ray photoemission spectroscopy (XPS) measurements were performed with monochromated Al Ka radiation. Valence band (VB) spectra of as-fractured SrTiO3 exhibit two peaks, Fl and P2, arising from the O 2p pi and O 2p sigma bonding orbitals, respectively. Upon adding 3.0 atm% of La to SrTiO3, the valley between P1 and P2 disappears in the VB spectrum, Calculated VB spectra obtained from a molecular orbital calculation reproduce well the experimental XPS spectra for the samples.

    DOI: 10.2109/jcersj.108.1257_518

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  • Difference of electronic structures between NaInO2 and NaInS2 査読 国際誌

    S Matsushima, S Kohiki

    Chemistry Letters   ( 1 )   8 - 9   2000年1月   ISSN:0366-7022 eISSN:1348-0715

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    The electronic structures of NaInO2 and NaInS2 are calculated by using the discrete variational X alpha method on model clusters. For NaInO2, it is found that the In-O bonding is not perfectly ionic but partially covalent because of the hybridization between O 2s, 2p and In 5s, 5p orbitals in the electron-occupied band. However, the overlapping of Na 3s, 3p orbitals with O 2s, 2p orbitals is very weak. On the other hand, Na 3s, 3p orbitals of NaInS2 relatively hybridize with S 3s, 3p orbitals, not only In 5s and 5p orbitals. These results show that the nature of the chemical properties of NaInS2 is more covalent, compared with NaInO2.

    DOI: 10.1246/cl.2000.8

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  • Preparation and characterization of NaInO2 and NaInS2 査読 国際誌

    K Fukuzaki, S Kohiki, S Matsushima, M Oku, T Hideshima, T Watanabe, S Takahashi, H Shimooka

    Journal of Materials Chemistry   10 ( 3 )   779 - 782   2000年   ISSN:0959-9428

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ROYAL SOC CHEMISTRY  

    NaInO2 and NaInS2 with alpha-NaFeO2 layer type structure have been prepared and characterized by X-ray photoelectron spectroscopy to clarify the role of the anions in the electronic structures of the compounds. The In 3d(5/2) binding energy for both compounds was the same, though the Na 1s binding energy of NaInO2 was larger than that of NaInS2 by 0.4 eV. The change in the Na Auger parameter, defined as the sum of Na 1s binding energy and KLL Auger kinetic energy, suggests that the difference in extra-atomic relaxation energy between the compounds causes the Na 1s binding energy shift. Discrete variational-X alpha model cluster calculations for NaInO2 and NaInS2 mirrored the experimental valence band spectra and the difference of 0.5 eV in optical absorption energy of the compounds. The cluster calculation revealed that in NaInO2 the highest occupied level is formed by an antibonding Na-O bond, whereas that in NaInS2 is formed by a bonding Na-S bond. The covalent Na-S bond decreases the extra-atomic relaxation energy for Na 1s electron emission from NaInS2.

    DOI: 10.1039/a908505j

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  • Semiempirical band calculation of Pd-adsorbed SnO2 surface 査読 国際誌

    S. Matsushima et al.

    Japanese Journal of Applied Physics Part 1   38 ( 9A )   4993 - 4996   1999年9月   ISSN:0021-4922

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:JAPAN J APPLIED PHYSICS  

    The electronic structure of a Pd-adsorbed SnO2 (001) surface is calculated using a semiempirical tight-binding method. When a Pd atom bridges two oxygen atoms on the SnO2 (001) surface, bonding and antibonding states arising from the admixture of Pd 4d and O 2p orbitals are formed around -15 eV and -8.35 eV. The energy levels of these bonding and antibonding states are overlapped with those of the valence and conduction bands. Nonbonding states originating from Pd 4d are calculated to be -9.2 eV and are located near the bottom of the conduction band of SnO2. The Fermi level of -8.37 eV is pinned at the nonbonding states with a large state density. When two Pd atoms are bound to two oxygen atoms on SnO2 (001), Pd-related states exhibit a bandlike character in spite of less than one monolayer coverage.

    DOI: 10.1143/JJAP.38.4993

    Web of Science

    J-GLOBAL

  • In2O3:Lix(x=0-1.0)の合成とキャラクタリゼーション 査読

    R Kiyoshima, S Kohiki, S Matsushima, M Oku

    日本化学会誌   ( 5 )   323 - 327   1999年5月   ISSN:0369-4577

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHEMICAL SOC JAPAN  

    Lithium-doped indium oxide crystals (In2O3 : Li-x, x=0-1.0) were synthesized by calcination in flowing oxygen of dried powders from aqueous solutions of InCl3 with Li. Only the peaks from cubic In2O3 crystal were observed in X-ray diffraction (XD). The lattice constant increased from 10.116 to 10.163 A, and the optical absorption energy decreased from 2.72 to 2.68 eV with increasing x in In2O3:Li-x. The lattice constant estimated by XD and the optical absorption edge in UV-visible absorption spectrometry remained at constants (10.163 Angstrom and 2.68 eV) in the region of x=0.5-1.0. Tight-binding (TB) band-structure calculations were performed for studying changes in the electronic structure with Li doping. The calculated energy splitting between the top of the valence band and the bottom of the conduction band decreased by Li doping at the empty sites (8a and 16c) of pure In2O3 crystal, which was consistent with the experimental decrements of the absorption energy with x in In2O3:Li-x. Changes in the valence band spectra by X-ray photoelectron spectroscopy of the In2O3:Li-x(x=0, 0.2 and 1.0) agree with that in the density of states by the TB calculation for two Li atoms doped at 8a or at 16c sites of In2O3 crystal. Doping of Li atoms into the interstitial sites affects both on the valence band and the conduction band minimum of the In2O3 crystal.

    DOI: 10.1246/nikkashi.1999.323

    Web of Science

  • Preparation and characterization of In2O3 : Lix(X=0-1.0) 査読

    Ryuta Kiyoshima, Shigemi Kohiki, Shigenori Matsushima, Masaoki Oku

    Nippon Kagaku Kaishi / Chemical Society of Japan - Chemistry and Industrial Chemistry Journal   ( 5 )   327   1998年   ISSN:0369-4577

     詳細を見る

    記述言語:日本語   掲載種別:研究論文(学術雑誌)  

    Lithium-doped indium oxide crystals (In2O3 : Lix, x=0-1.0) were synthesized by calcination in flowing oxygen of dried powders from aqueous solutions of InCl3 with Li. Only the peaks from cubic In2O3 crystal were observed in X-ray diffraction (XD). The lattice constant increased from 10.116 to 10.163 Å, and the optical absorption energy decreased from 2.72 to 2.68 eV with increasing x in In2O3 : Lix. The lattice constant estimated by XD and the optical absorption edge in UV-visible absorption spectrometry remained at constants (10.163 Å and 2.68 eV) in the region of x=0.5-1.0. Tight-binding (TB) band-structure calculations were performed for studying changes in the electronic structure with Li doping. The calculated energy splitting between the top of the valence band and the bottom of the conduction band decreased by Li doping at the empty sites (8a and 16c) of pure In2O3 crystal, which was consistent with the experimental decrements of the absorption energy with x in In2O3 : Lix. Changes in the valence band spectra by X-ray photoelectron spectroscopy of the In2O3 : Lix(x=0, 0.2 and 1.0) agree with that in the density of states by the TB calculation for two Li atoms doped at 8a or at 16c sites of In2O3 crystal. Doping of Li atoms into the interstitial sites affects both on the valence band and the conduction band minimum of the In2O3 crystal.

    Scopus

  • Preparation of Perovskite-Type Oxides by the Thermal Decomposition of Heteronuclear Complexes, Ln[Fe_xCo_<1-x>(CN)_6]・4H_2O(Ln=Pr-Yb) 査読 国際誌

    坂本 政臣, Nunziante Patrizia, Traversa Enrico, 松嶋 茂憲, 三輪 昌作, 青野 宏通, 定岡 芳彦

    Journal of the Ceramic Society of Japan   105 ( 1227 )   963 - 969   1997年11月   ISSN:0914-5400

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人日本セラミックス協会  

    Heteronuclear complexes of Ln[Fe_xCo_&lt;1-x&gt;(CN)_6]・4H_2O (Ln=Pr-Yb) were synthesized and their thermal decomposition products were investigated. Thermal decomposition of the complexes results in the formation of perovskite-type oxides for Ln=Pr-Gd even at 800℃. The lattice parameters, a-, b- and c-lattice constants (crystal system: orthorhombic) increase linearly with the ratio of Fe/Co for the perovskite-type oxide. For Ln=Dy through Yb, the Ln_2O_3 phase is observed as the major product for x=0, but its content decreased with an increase in the Fe content; however, a single phase of the perovskite-type oxide was not formed for x=1. The perovskite-type structure for the Fe systems is easier to form compared with the Co systems. We clarified that the formation of the perovskite-type oxide is mainly affected by the ionic radius of the Ln^&lt;3+&gt; ion and the T^&lt;3+&gt; ion (T=Fe or Co).

    DOI: 10.2109/jcersj.105.963

    CiNii Books

  • Thermal decomposition products of heteronuclear complexes, CuRe(dhben)(NO3・nH2O, (RE=La, Eu, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb, and Lu) 査読 国際誌

    Journal of Alloys and Compounds   260   59 - 63   1997年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Preparation of ZnO films on sapphire (01-12) substrates by low-pressure organometallic chemical vapour deposition 査読 国際誌

    Journal of Materials Science Letters   15 ( 5 )   457 - 459   1996年3月   ISSN:0261-8028

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:CHAPMAN HALL LTD  

    Web of Science

    Scopus

  • Surface states due to Fe atoms deposited on a TiO2 surface coated with a porous SiO2 film 査読 国際誌

    The Journal of Physical Chemistry   100   7106 - 7113   1996年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • An impedance analysis of an oxygen-sensitive ZnO-SiO2-Au device under UV illumination 査読 国際誌

    K KOBAYASHI, H NAKATA, S MATSUSHIMA, G OKADA

    The Journal of Physical Chemistry   99 ( 3 )   999 - 1004   1995年1月   ISSN:0022-3654

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER CHEMICAL SOC  

    Resistance and capacitance of the ZnO-SiO2-Au device appreciably respond to changes in O-2 partial pressure under strong UV illumination (10 mW/cm(2)). From complex impedance plots under the strong UV illumination, values of resistance of the ZnO film are estimated to be 300 and 50 k Omega in Oz and in Ar, respectively, and values of resistance of the ZnO-SiO2 interface at 0 V are estimated to be 1000 and 280 k Omega in O-2 and in Ar, respectively. Plots of Cp(-2) vs V in the dark, where C-p is the capacitance of the ZnO-SiO2 interface and V is a bias voltage, indicate that the band bending in O-2 is larger than that in Ar by 0.25 eV;and that the carrier density (5 x 10(17) cm(-3)) of the ZnO film in O-2 is the same as in Ar. When the UV illumination is turned off, a remarkable recovery of resistance measured at 100 Hz is observed at -2 and 0 V in Oz, while no recovery is observed in Ar. The response of the resistances of both the ZnO film and the ZnO-SiO2 interface to changes in the Oz partial pressure is ascribed to a change in the band bending caused by adsorption and photon-stimulated desorption of oxygen.

    Web of Science

  • Effect of electric field on transmission spectra of a four-layer film consisting of Ga-doped ZnO, undoped-ZnO, SiO2, and Ga-doped ZnO 査読

    Denki Kagaku   63   527 - 528   1995年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • NO2 sensing properties of thick Zn2SnO4 film 査読 国際誌

    Journal of the Ceramic Society of Japan   103   302 - 303   1995年   ISSN:0914-5400

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    担当区分:筆頭著者, 最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Ceramic Soc of Japan  

    Thick Zn2SnO4 films have the highest sensitivities to NO2 among the examined complex oxides with spinel structure. Although the NO2gas sensitivities of thick Zn2SnO4 films decrease with increasing temperature, high sensitivities are obtained in the temperature range of 573 to 673 K. The sensitivities of the present Zn2SnO4 films are comparable to those of NO2-sensitive oxides such as WO3 and ZnO.

    DOI: 10.2109/jcersj.103.302

    Scopus

  • Preparation of c-axis oriented ZnO films by low-pressure organometallic chemical vapor deposition 査読 国際誌

    Tjin Solid Films   266   106-109   1995年

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Detection of bulk deep traps at the TiO2/H2O interface by isothermal capacitance transient spectroscopy 査読

    Denki Kagaku   62   538 - 539   1994年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • 酸化鉄の微細構造とNO2検知特性 査読

    日本セラミックス協会論文誌   102   185 - 188   1994年

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    担当区分:筆頭著者   記述言語:日本語   掲載種別:研究論文(学術雑誌)  

  • Photoinduced charge transfer of Cu-doped ZnO film 査読 国際誌

    Journal of Materials Science Letters   13   103 - 104   1994年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Electrical properties of Y-doped CaCuO2 films prepared by organometallic chemical vapor deposition 査読 国際誌

    Applied Physics Letters   62   2868 - 2870   1993年

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    掲載種別:研究論文(学術雑誌)  

  • NO2 gas-sensing properties of Ga-doped ZnO thin film 査読 国際誌

    Sensors and Actuators B   13-14   62 - 622   1993年

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Localization of carriers of Y-doped CaCuO2 films prepared by an organometallic chemical vapor deposition method 査読 国際誌

    Journal of Materials Science   28   6699 - 6703   1993年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Growth of ZnO films by low-pressure organometallic chemical vapor deposition 査読 国際誌

    Thin Solid Films   235   20 - 21   1993年

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Valence states of cobalt ions in a sputtered ZnO film 査読 国際誌

    Journal of Materials Science Letters   12   168 - 169   1993年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • TiをドープしたFe2O3薄膜のNO2検知特性 査読

    松嶋 茂憲, 小林 健吉郎, 岡田 元次

    電気化学   61 ( 6 )   680 - 682   1993年   ISSN:1344-3542

     詳細を見る

    担当区分:筆頭著者, 責任著者   記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:電気化学会  

    CiNii Books

  • Preparation of ZnO films by low-pressure organometallic chemical vapor deposition 査読 国際誌

    KOBAYASHI Kenkichiro, MATSUBARA Toshihiro, MATSUSHIMA Shigenori, OKADA Genji

    Chemistry Letters   1993 ( 12 )   2133 - 2136   1993年   ISSN:0366-7022

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    CiNii Books

  • Mechanism of photoinduced charge transfer o Cu-doped ZnO film in strong electric field 査読 国際誌

    Japanese Journal of Applied Physics   32   3854 - 3859   1993年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • NO2-sensitive LaFeO3 film prepared by thermal decomposition of the heteronuclear complex, {La[Fe(CN)6・5H2O}x 査読 国際誌

    Journal of Materials Chemistry   3   767 - 769   1993年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Mechanism of photoinduced charge transfer in Co(Li)-doped ZnO film 査読 国際誌

    Japanese Journal of Applied Physics   31   1079 - 1082   1992年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Development of SnO2-based ethanol gas sensor 査読 国際誌

    Sensors and Actuators B   9   63 - 69   1992年

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • New method for supporting palladium on a tin oxide gas sensor 査読 国際誌

    Sensors and Actuators B   9   71 - 78   1992年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • H2La2Ti3O10におけるプロトンの挙動 査読

    電気化学   60   336 - 338   1992年

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)  

  • NO2 sensitive Ga-doped ZnO thin film 査読 国際誌

    Chemistry Letters   1992   323 - 326   1992年

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Optical and electronic properties of cobalt-doped zinc oxide films prepared the sputtering method 査読 国際誌

    Journal of Materials Science   27   5953 - 5957   1992年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Oxygen-sensing properties of sputtered ZnO film deposited on sapphire under ultraviolet illumination 査読 国際誌

    Journal of Materials Science Letters   11   1389 - 1391   1992年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Electrical and optical properties of Ca1-xSrxCuO2 films prepared by organometallic vapor deposition method 査読 国際誌

    Japanese Journal of Applied Physics   30   1931 - 1934   1991年

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    掲載種別:研究論文(学術雑誌)  

  • Formation of the pseudo-tetragonal phase by hydrogenation of Nd2CuO4 at a low temperature 査読 国際誌

    Journal of Materials Science Letters   10   1386 - 1388   1991年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Structure and copper valence of hydrogen-doped Nd2CuOxHy 査読 国際誌

    Journal of Materials Science Letters   10   523 - 525   1991年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Ethanol gas sensing properties of Pd-La2O3-In2O3 thick film element 査読 国際誌

    Chemistry Letters   1990   477 - 480   1990年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • An oxygen sensitive ZnO-SiO2-Au device under UV irradiation 査読

    Denki Kagaku   58   1220 - 1222   1990年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Role of additives on alcohol sensing by semiconductor gas sensor 査読 国際誌

    Chemistry Letters   1989   845 - 848   1989年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Electronic interaction between metal additives and tin dioxide in tin dioxide-based gas sensors 査読 国際誌

    Japanese Journal of Applied Physics   27   1798 - 1802   1988年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • CO sensitive Pt/SnO2 diode type gas sensor 査読 国際誌

    S. Matsushima et al.

    Chemistry Letters   1987   2001 - 2004   1987年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • Doping of Fe to In2O3 査読 国際誌

    Thin Solid Films   505 ( 1-2 )   122 - 125   2006年5月   ISSN:0040-6090

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE SA  

    Model cluster calculations by discrete variational-X alpha method for the Fe3+ ions at 8b and 24d sites of the In2O3 crystal lattice demonstrated that the density of states of the Fe3+ 3d electrons located around the center of the band gap, and the spin density of states for the Fe3+ ions at 8b and 24d sites are asymmetric. For Fe-doped In2O3 powders, we found a cusp at approximate to 30 K overlapping cluster glass behavior in dc susceptibility, though the Cusp showed no frequency dependence in ac susceptibility. The cusp at approximate to 30 K for the Fe-doped In2O3 powders can be attributed to superexchange interactions between Fe3+ ions substituted for In3+ ions of the In2O3 crystal lattice. (c) 2005 Elsevier B.V All rights reserved.

    DOI: 10.1016/j.tsf.2005.10.022

    Web of Science

    J-GLOBAL

  • Cu doping effects on optical and magnetic properties of In2O3 査読

    Masakuni Sasaki, Kimihiro Yasui, Shigemi Kohiki, Hiroyuki Deguchi, Shigenori Matsushima, Masaoki Oku, Toetsu Shishido

    Journal of Alloys and Compounds   334 ( 1-2 )   205 - 210   2002年2月   ISSN:0925-8388

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Doping of Cu to In2O3 brought about growth of a new state in the bandgap and decrement of the bandgap energy with an increase of the nominal molar ratio x( = [Cu]/[In2O3]&lt
    1) in the ultraviolet-visible (UV-vis) optical absorption spectra. A superconducting quantum interference device magnetometer was used for magnetic susceptibility measurement. The sample x = 0.5 showed antiferromagnetism with Neel temperature of ∼30 K. In addition to the antiferromagnetism, paramagnetic behavior was also observed for the sample x = 1. First-principles molecular-orbital calculation with a model cluster for Cu2+ ion at the 8a site of the In2O3 crystal showed the density of states (DOS) mirroring the new in-gap state accompanied with the narrowing energy gap. In the model cluster, calculations of Cu2+ ions for the 8a and 16c sites showed the asymmetric and symmetric Cu 3d spin DOS corresponding to the antiferromagnetism and paramagnetism, respectively. © 2002 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0925-8388(01)01760-1

    Scopus

▼全件表示

書籍等出版物

  • 光触媒:基礎・材料開発・応用

    町田正人, 松嶋茂憲(担当:分担執筆 範囲:第2編第2章5. 層状酸化物光触媒による水の完全分解反応)

    エヌ・ティー・エス  2005年5月 

     詳細を見る

    記述言語:日本語   著書種別:学術書

  • DV-Xα法による酸化物固体の電子構造計算

    2000年12月 

  • d-f元素系ヘテロ金属錯体を出発原料とするペロブスカイト超微粒子の調製とキャラクタリゼーション

    マツダ財団研究報告書  1997年 

  • Development of Oxide Thin Films Sensitie to NO2

    1995年 

講演・口頭発表等

  • Fe-doped In2O3希薄磁性体の合成とキャラクタリゼーション

    村川ら

    日本化学会中国四国支部・同九州支部合同大会  2001年10月 

     詳細を見る

    会議種別:口頭発表(一般)  

  • NASICON-based CO2 sensor operative at room temperature with Li2CO3-based auxiliary as a sensing electrode 国際会議

    K.Obata, S.Matsushima

    14 th Internatinal Meeting on Chemical Sensors (in Nuremberg, Germany)  2012年5月 

     詳細を見る

    記述言語:英語   会議種別:ポスター発表  

  • NaInO2の合成とキャラクタリゼーション

    福崎ら

    第60回応用物理学学術講演会  1999年9月 

     詳細を見る

    記述言語:日本語   会議種別:口頭発表(一般)  

  • Mn-doped ZnGa2O4に関する固体電子構造計算

    谷崎 巧, 松嶋茂憲, 水野正隆, 徐 超男

    日本化学会中国四国支部・同九州支部合同大会  2001年10月 

     詳細を見る

    記述言語:日本語   会議種別:口頭発表(一般)  

  • Mn-doped In2O3の合成とその特性

    鈴鹿ら

    秋季第63回応用物理学会学術講演会  2002年9月 

     詳細を見る

    記述言語:日本語   会議種別:口頭発表(一般)  

  • LiInO2の電子構造

    田畑ら

    第38回化学関連支部合同九州大会  2001年7月 

     詳細を見る

    記述言語:日本語   会議種別:ポスター発表  

  • Invstigation of dye-sensitized solar cells with high photovoltanic efficiency by ion-implantation treatment 国際会議

    The 12th IUPAC International Symposium on MacroMolecular Complexes (MMC-12)  2007年8月 

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    記述言語:英語   会議種別:ポスター発表  

  • In2O3:Liの合成とキャラクタリゼーション

    清島ら

    第36回化学関連支部合同九州大会  1999年7月 

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    記述言語:日本語   会議種別:ポスター発表  

  • In2O3:Lix(x = 0 ~ 1.0)のキャラクタリゼーション

    佐々木ら

    第35回X線分析討論会  1999年11月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3:Cu希薄磁性体

    佐々木ら

    日本化学会中国四国支部・同九州支部合同大会  2001年10月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3:Cux(x=0~1)の合成とキャラクタリゼーション

    佐々木ら

    第37回化学関連支部合同九州大会  2000年7月 

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    記述言語:日本語   会議種別:ポスター発表  

  • In2O3希薄磁性半導体

    佐々木ら

    2001年春季応用物理学関係連合講演会  2001年3月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3厚膜のCO検知特性

    長野 桂, 松嶋茂憲

    第37回化学関連支部合同九州大会  2000年7月 

     詳細を見る

    記述言語:日本語   会議種別:ポスター発表  

  • In2O3へのLi添加効果

    清島ら

    第60回応用物理学学術講演会  1999年11月 

     詳細を見る

    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3へのLiドーピング効果

    佐々木ら

    H11年度応用物理学会九州支部講演会  1999年11月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3へのLiドーピング

    清島ら

    第46回応用物理学関係連合講演会  1999年3月 

     詳細を見る

    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3へのFe添加効果

    安井ら

    第38回化学関連支部合同九州大会  2001年7月 

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    記述言語:日本語   会議種別:ポスター発表  

  • In2O3へのFeドーピング

    村川ら

    秋季第63回応用物理学会学術講演会  2002年9月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3へのCuドーピング効果

    佐々木ら

    平成12年度応用物理学九州支部講演会  2000年12月 

     詳細を見る

    記述言語:日本語   会議種別:口頭発表(一般)  

  • In2O3へのCuドーピング効果

    佐々木ら

    春季第47回応用物理学関係連合講演会  2000年3月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • Preparation and characterization of MFe2O4 (M = Mg, Ca) prepared from a malic acid complex 国際会議

    A. Doi, M. Inenaga, R. Maeda, K. Obata, S.Matsushima

    The 30th Japan-Korea International Seminar on Ceramics (in Kitakyushu, Japan)  2013年11月 

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    記述言語:英語   会議種別:ポスター発表  

  • Growth of p-type ZnOS Films by Pulsed Laser Deposition 国際会議

    X. Zhan, K. Kobayashi, Y. Kohno, Y. Tomita, Y. Maeda, S. Matsuhima

    IUMRS-ICA 2013, ABS-296-ICA (in India)  2012年12月 

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    記述言語:英語   会議種別:ポスター発表  

  • Effect of Eu doping on the electronic structure of SrAl2O4

    Y. Obukuro, S. Matsushima, M. Mizuno, H. Yamada, C.N. Xu

    Mechanoluminescence and Novel Structure Health Diagnosis 2011  2011年11月 

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    記述言語:英語   会議種別:ポスター発表  

  • Effect of another element on CO2 sensing properties of CaFe2O4 国際会議

    K. Obata, K. Mizuta, Y. Obukuro, S. Matsushima

    The 12th Asian Conference on Chemical Sensors  2017年11月 

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    記述言語:英語   会議種別:ポスター発表  

  • CuMgVO4 の固体電子構造

    猪原由香, 我毛智哉, 松嶋茂憲, 新井正男

    第54回化学関連支部合同九州大会  2017年7月 

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    記述言語:日本語   会議種別:ポスター発表  

  • Characterization of magnesium ferrite prepared from a malic acid complex 国際会議

    Y. Obukuro, K. Obata, S.Matsushima, M. Arai, K. Kobayashi

    The 15th IUMRS-International Conference in Asia (IUMRS-ICA 2014)  2014年8月 

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    記述言語:英語   会議種別:ポスター発表  

  • Characterization and photocatalytic activity for La-doped Sr2Bi2O5 Oxides 国際会議

    Y. Obukuro, S. Matsushima, K. Obata, K. Sasaki, E. Asato, N. Matayoshi

    The 15th IUMRS-International Conference in Asia (IUMRS-ICA 2014).  2014年8月 

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    記述言語:英語   会議種別:口頭発表(一般)  

  • CaBi2O4の合成

    第45回  2008年7月 

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    会議種別:ポスター発表  

  • Ca2Fe2O5における不純物のi添加効果

    熊谷貴史, 土居茜, 小畑賢次, 松嶋茂憲

    日本セラミックス協会九州支部主催 平成26年度九州支部秋季合同研究発表会  2014年11月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • Bi2CuO4に関する第一原理エネルギーバンド計算

    第46回セラミックス基礎科学討論会  2008年1月 

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    会議種別:口頭発表(一般)  

  • BaTiS3に関する第一原理分子軌道計算

    野中壮泰, 松嶋茂憲

    2000年3月 

     詳細を見る

    会議種別:口頭発表(一般)  

  • AMgVO4 (A = Cu, Ag) に関する第一原理エネルギーバンド計算

    我毛智哉, 猪原由香, 植田泰平, 小畑賢次, 新井正男, 松嶋茂憲

    電気化学会第84回大会  2017年3月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • AgMgVO4 の固体電子構造

    植田泰平, 我毛智哉, 松嶋茂憲, 新井正男

    第54回化学関連支部合同九州大会  2017年7月 

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    記述言語:日本語   会議種別:ポスター発表  

  • Addition effect of multivalent cation on CO sensing properties of MgFe2O4 nanopowder 国際会議

    K. Obata, S. Matsushima

    The 28th Annual Meeting of MRS-J  2018年12月 

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    記述言語:英語   会議種別:ポスター発表  

  • CO2 sensing properties of Zr-added CaFe2O4-based sensor 国際会議

    Y. Obukuro, K. Mizuta, K. Obata, S. Matsushima

    The 12th Asian Conference on Chemical Sensors  2017年11月 

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    記述言語:英語   会議種別:ポスター発表  

  • (M, V)-doped ZrO2 (M = Al, Y, La) に関する第一原理バンド計算

    岡上蒼士, 中村光騎, 松嶋茂憲, 石井純子, 新井正男, 小畑賢次

    第60回化学関連支部合同九州大会  2023年7月 

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    記述言語:日本語   会議種別:ポスター発表  

  • Effect of Ti-doping in CaFe2O4 prepared from a malic acid complex 国際会議

    A. Doi, M. Nomura, T. Okawara, K. Obata, S.Matsushima

    4th Asian Conference on Coordination Chemistry (in Korea)  2013年11月 

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    記述言語:英語   会議種別:ポスター発表  

  • Effects of doped TiO2 electrode on energy conversion efficiency in dye-sensitized solar cell

    The 10th Pacific Polymer Conference  2007年12月 

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    記述言語:英語   会議種別:口頭発表(一般)  

  • Energy band calculation of Sr2Bi2O5 crystal based on modified Becke-Johnson exchange potential 国際会議

    Y. Obukuro, K. Obata, S.Matsushima, M. Arai, K. Kobayashi

    The 30th Japan-Korea International Seminar on Ceramics (in Kitakyushu, Japan)  2013年11月 

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    記述言語:英語   会議種別:ポスター発表  

  • Photocatalytic activity of TiO2 particles surface-modified by plasma CVD 国際会議

    The 10th Pacific Polymer Conference  2007年12月 

     詳細を見る

    記述言語:英語   会議種別:口頭発表(一般)  

  • MgFe2O4におけるLaの導入効果

    平野達也, 土居茜, 小畑賢次, 鈴木拓, 西堀麻衣子, 島ノ江憲剛, 松嶋茂憲

    第53回化学関連支部合同九州大会  2016年7月 

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    記述言語:日本語   会議種別:ポスター発表  

  • MgFe2-xLaxO4 を用いた CO センサにおける水蒸気の影響

    生駒優太, 小畑賢次, 松嶋茂憲

    2021年度 日本セラミックス協会九州支部 秋季研究発表会  2021年11月 

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    記述言語:日本語   会議種別:口頭発表(一般)  

  • NASICON(Na(1+x)Zr2SixP(3-x)O12)を用いた起電力式ガスセンサのCO2特性

    第20回日本セラミックス協会秋季シンポジウム  2007年9月 

     詳細を見る

    会議種別:口頭発表(一般)  

  • NASICONを用いた起電力式ガスセンサのCO2検知特性

    第18回九州沖縄地区高専フォーラム  2009年1月 

     詳細を見る

    会議種別:口頭発表(一般)  

  • NASICONを用いた起電力式CO2センサの起電力とエージング処理との関係

    第15回九州夏季セラミックス研究会  2008年8月 

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    会議種別:口頭発表(一般)  

  • NASICOnを用いた起電力式CO2センサのエージング処理と起電力との関係

    第21回日本セラミックス協会秋季シンポジウム  2008年9月 

     詳細を見る

    会議種別:口頭発表(一般)  

  • M3Ta6Si4O26(M = Sr, Ba)に関する固体電子構造解析

    我毛智哉, 二宮翔, 松嶋茂憲, 新井正男

    第5回CSJ化学フェスタ2015  2015年10月 

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    記述言語:日本語   会議種別:ポスター発表  

  • M-doped ZnGa2O4 (M=Mn, Fe, Co, Ni)に関する固体電子構造計算

    野中壮泰, 松嶋茂憲, 水野正隆, 徐 超男

    第21回電子材料研究討論会  2001年10月 

     詳細を見る

    会議種別:口頭発表(一般)  

  • In2-xMnxO3の合成とキャラクタリゼーション

    鈴鹿ら

    第38回化学関連支部合同九州大会  2001年7月 

     詳細を見る

    会議種別:ポスター発表  

  • in-situ 赤外分光法と第一原理計算を用いたY型ゼオライト中での二酸化炭素吸着に関する研究

    安村駿作, 浦川篤, 松嶋茂憲

    平成29年度 セラミックス協会九州支部秋季合同研究発表会  2017年11月 

     詳細を見る

    記述言語:日本語   会議種別:口頭発表(一般)  

▼全件表示

MISC

  • Comparison of Stability of Metals Adsorbed on SiC Surfaces: A First-Principles Study 査読

    Junko Ishii, Shigenori Matsushima

    北九州工業高等専門学校研究報告   2023年1月

     詳細を見る

    担当区分:最終著者   記述言語:英語   掲載種別:記事・総説・解説・論説等(大学・研究所紀要)  

  • Laを添加したMgFe2O4系COセンサにおける水蒸気の影響 査読

    小畑賢次, 松嶋茂憲

    北九州工業高等専門学校研究報告   54   43 - 46   2021年1月

     詳細を見る

    担当区分:最終著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)  

  • MgFe2-xLaxO4 (0.05 ≤ x ≤0.2) におけるCOガス検知 査読

    小畑賢次, 松嶋茂憲

    北九州工業高等専門学校研究報告   53   69 - 74   2020年1月

     詳細を見る

    担当区分:最終著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)  

  • MgとVを共ドープしたY2Ti2O7の固体電子構造解析 査読

    松嶋茂憲, 石井純子, 小畑賢次

    北九州工業高等専門学校研究報告   53   45 - 48   2020年1月

     詳細を見る

    担当区分:筆頭著者, 責任著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)  

  • MgFe2O4の微細構造における異種元素の添加効果 査読

    松嶋茂憲, 小畑賢次, 土居 茜, 平野達也, 野末皓平

    北九州工業高等専門学校研究報告   50   53 - 60   2017年1月

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    担当区分:筆頭著者, 責任著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)  

  • 高比表面積を持つビスマス系およびフェライト系複合酸化物の調製 (特集 KOSEN(高専)発セラミックスイノベーション : 次世代の産業貢献を目指して) 招待

    松嶋 茂憲, 小畑 賢次

    Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan   51 ( 5 )   305 - 309   2016年5月   ISSN:0009-031X

     詳細を見る

    担当区分:筆頭著者, 責任著者   記述言語:日本語   掲載種別:記事・総説・解説・論説等(学術雑誌)   出版者・発行元:日本セラミックス協会  

    CiNii Books

  • Ba3Ta6Si4O26に関する固体電子構造解析 査読

    我毛智哉, 二宮 翔, 中村裕之, 松嶋茂憲

    北九州工業高等専門学校研究報告   49   45 - 48   2016年1月   ISSN:2185-7598

     詳細を見る

    担当区分:最終著者, 責任著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)   出版者・発行元:北九州工業高等専門学校  

    CiNii Books

  • CO2共存下における室温作動型固体電解質NO2センサのガス選択性の改善 査読

    小畑賢次, 松嶋茂憲

    北九州工業高等専門学校研究報告   48   89 - 94   2015年1月   ISSN:2185-7598

     詳細を見る

    担当区分:最終著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)   出版者・発行元:北九州工業高等専門学校  

    CiNii Books

  • Ca4Bi6O13へのSrのドープ効果 査読

    小畑賢次, 上原拓也, 松嶋茂憲

    北九州工業高等専門学校研究報告   45   81 - 86   2012年1月   ISSN:2185-7598

     詳細を見る

    担当区分:最終著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)   出版者・発行元:北九州工業高等専門学校  

    CiNii Books

  • NASICON(Na1+xZr2Si2PO12:0<x<3)を用いた起電力式CO2センサのガス検知特性

    小畑 賢次, 松嶋 茂憲

    Proceedings of the Chemical Sensor Symposium   47   4 - 6   2009年3月

     詳細を見る

    担当区分:最終著者   記述言語:日本語   掲載種別:研究発表ペーパー・要旨(全国大会,その他学術会議)   出版者・発行元:電気化学会化学センサ研究会  

  • NASICON(Na1+XZr2SiXP3-XO12 :x=1,15,2,2.75)を用いた起電力式ガスセンサのエージング処理と起電力との関係 査読

    小畑賢次, 松嶋茂憲

    北九州工業高等専門学校研究報告   42   93 - 98   2009年1月

     詳細を見る

    担当区分:最終著者   記述言語:日本語   掲載種別:速報,短報,研究ノート等(大学,研究機関紀要)  

  • NASICONを用いた室温作動型CO2センサの参照極材料の検討

    小畑 賢次, 熊澤 志津子, 松嶋 茂憲

    Proceedings of the Chemical Sensor Symposium   38   34 - 36   2004年3月

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    担当区分:最終著者   記述言語:日本語   出版者・発行元:電気化学会化学センサ研究会  

  • Electronic structure of M-doped ZnGa2O4 (M = Mn, Fe, Co, Ni) spinel using DV-X alpha method 国際誌

    M Nonaka, S Matsushima, M Mizuno, CN Xu

    ASIAN CERAMIC SCIENCE FOR ELECTRONICS II AND ELECTROCERAMICS IN JAPAN V, PROCEEDINGS   228-2   303 - 306   2002年   ISSN:1013-9826

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    担当区分:責任著者   記述言語:英語   出版者・発行元:TRANS TECH PUBLICATIONS LTD  

    Molecular orbital (MO) calculations were carried out by the DV-Xalpha method to clarify the effect of an impurity on the electronic structures of ZnGa2O4 crystal. In the calculation for M-doped ZnGa2O4 (M being one of the following metals: Mn, Fe, Co, Ni), the new energy states originating from M 3d orbitals appear in the band gap. The gap states split into two energies; the lower state is doubly degenerate c states, the higher one being triply degenerate t(2) states, as predicted by the ligand field theory. These levels tend to decrease in energy as the atomic number of the transition metal ion increases. Furthermore, M-O bonding becomes more covalent with increasing the atomic number of the transition metal ion.

    Web of Science

  • CO Gas Sensing Properties of Thick In2O3 Film 査読

    Research Report of Kitakyushu National College of Technology   vol. 35, 89-92   2002年

  • In2O3 based diluted magnetic semiconductor

    M.Sasaki, S.Matsushima, H.Deguchi, M.Oku, T.Shishido, K.Shimooka, S.Takahashi, S.Kohiki

    DV-Xα International Workshop ('01) & 14th Annual Meeting of the Society for DV-Xα Japan   Mater-13   2001年

  • Energy Band Calculation of Titanium Dioxide

    Research Report of Kitakyushu National College of Technology   32   155 - 159   1999年

  • Energy band calculation of Ag-adsorbed SnO2 surface 国際誌

    S. Matsushima, K. Kobayashi, M. Kohyama

    International Society of Electrochemistry, 49th Annual Meeting Extended Abstracts   49   905   1998年

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    担当区分:筆頭著者, 責任著者   記述言語:英語  

  • Pd-adsorbed SnO2表面に関する半経験的バンド計算(Ⅰ)

    松嶋茂憲, 原口俊秀, 小林健吉郎, 白方 祥, 香山正憲

    第24回化学センサ研究発表会プロシーディング   1997年3月

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    担当区分:筆頭著者, 責任著者   記述言語:日本語   掲載種別:研究発表ペーパー・要旨(全国大会,その他学術会議)  

  • Application of semi-empirical tight-binding method to band calculation of chalcopyrite semiconductors

    Shirakata Sho, Matsushima Shigenori, Isomura Shigehiro, Masanori Kohyama

    愛媛大学工学部紀要   16   83 - 100   1997年   ISSN:0285-6107

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    記述言語:英語   出版者・発行元:愛媛大学  

    CiNii Books

  • Filed-Assisted Photochromism of ZnO Film Doped with Transition Metal Ions 国際誌

    Proceeding of Japan-U. S. Workshop on Fuctional Frons in Advanced Ceramics (Boundary and Defects)   177-   1994年

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    記述言語:英語  

  • Control of Pd Dispersion in SnO2-based Sensors

    Catalytic Science and Technology   1   1990年

  • Dispersion State of Pd Particles and Sensing Properties in Pd-SnO2 Sensors

    Shokubai   32 ( 6 )   1990年

  • Adsorption Behavior of CO and NOx on SnO2 Based Gas Sensor Element

    Technical Digest of the 8th Sensor Symposium   1989年

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    記述言語:英語   掲載種別:記事・総説・解説・論説等(国際会議プロシーディングズ)  

  • Control of Alcohol Sensing Properties in SnO2-based Semiconductor Gas Sensor 国際誌

    Proceeding of the 40th ISE Meeting   1   1989年

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    記述言語:英語   掲載種別:記事・総説・解説・論説等(国際会議プロシーディングズ)  

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  • DV-Xα研究会

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