Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Miki Inada Last modified date:2019.06.28

Associate Professor / Center of Advanced Instrumental Analysis

1. Angga Hermawan, Yusuke Asakura, Miki Inada, Shu Yin, One-step synthesis of micro-/mesoporous SnO2 spheres by solvothermal method for toluene gas sensor, Ceramics International, 10.1016/j.ceramint.2019.05.043, 45, 12, 15435-15444, 2019.08, A facile solvothermal synthesis in an ethanol/acetic acid mixture for the fabrication of SnO2 with a controllable hierarchical spherical size and micro-/mesoporosity is presented. SEM, TEM and N2 adsorption/desorption investigation unveiled that the obtained SnO2 spheres exhibited a particle size in the range of 0.6–1.6 μm and a pore size of about 1.4–1.9 nm depending on the volume ratio of acetic acid to ethanol in the reaction mixture, and the spheres were constructed by nanoscale particles. Due to its micro-/mesoporous structure, the SnO2 spheres exhibited large specific surface areas over 100 m2/g. When 10 vol. % of acetic acid at 200 °C for 20 h was used for the reaction, the obtained SnO2 possessed a higher specific surface area of 145 m2/g (SnO2_10). The gas sensing property of SnO2_10 without an additional noble metal co-catalyst exhibited a large toluene sensing response (Ra/Rg) of 20.2 at 400 °C, which was about 6 times higher and acceptable selectivity compared to those of other samples. The study found that the sensing performance in the SnO2 hierarchical spheres was influenced by several factors e.g. particle morphology, pore size and specific surface area rather than only a single parameter. Therefore, a precise control of those influencing parameters may lead to the optimum sensing property. These findings are important for the further development of the micro-/mesoporous metal-based oxide as an alternative successor for toluene gas sensor material..
2. Shingo Hirata, Miki Inada, Naoya Enomoto, Katsuro Hayashi, Junichi Hojo, Kinetic approach for the adsorption-photodecomposition properties of mesoporous silica-titania, Journal of the Ceramic Society of Japan, 10.2109/jcersj2.19003, 127, 4, 242-248, 2019.04, We have fabricated mesoporous silica-titania by a solgel method and evaluated the photocatalytic activity using acetaldehyde. The synthesized mesoporous silica-titania was effective for the removal of acetaldehyde from gas phase by adsorption and photodecomposition. In this study, the kinetic approach was carried out in order to clarify the adsorption-photodecomposition property of mesoporous silica-titania. The adsorption, direct photodecomposition and concerted adsorption-photodecomposition can be separately described in our simulation curves, which indicates that the adsorbability strongly affects the removal of acetaldehyde in the early stage and the photodecomposition after the strong adsorption of acetaldehyde on mesoporous silica-titania is important for the complete removal of acetaldehyde from gas phase..
3. Yasuhiro Uchida, Joji Hasegawa, Kazunari Shima, Miki Inada, Naoya Enomoto, Hirofumi Akamatsu, Katsuro Hayashi, Insights into Sodium Ion Transfer at the Na/NASICON Interface Improved by Uniaxial Compression, ACS Applied Energy Materials, 10.1021/acsaem.9b00250, 2, 4, 2913-2920, 2019.04, A robust ceramic solid electrolyte with high ionic conductivity is a key component for all-solid-state batteries (ASSBs). In terms of the demand for high-energy-density storage, researchers have been tackling various challenges to use metal anodes, where a fundamental understanding on the metal/solid electrolyte interface is of particular importance. The Na
superionic conductor, so-called NASICON, has high potential for application to ASSBs with a Na anode due to its high Na
ion conductivity at room temperature, which has, however, faced a daunting issue of the significantly large interfacial resistance between Na and NASICON. In this work, we have successfully reduced the interfacial resistance as low as 14 ω cm
at room temperature by a simple mechanical compression of a Na/NASICON assembly. We also demonstrate a fundamental study of the Na/NASICON interface in comparison with the Na/β′′-alumina counterpart by means of the electrochemical impedance technique, which elucidates a stark difference between the activation energies for interfacial charge transfer: ∼0.6 eV for Na/NASICON and ∼0.3 eV for Na/β′′-alumina. This result suggests the formation of a Na
-conductive interphase layer in pressing Na metal on the NASICON surface at room temperature..
4. Joji Hasegawa, Kei Kawahara, Kazunari Shima, Miki Inada, Naoya Enomoto, Katsuro Hayashi, Characterization of an AX Compound Derived from Ti
SC MAX Phase, European Journal of Inorganic Chemistry, 10.1002/ejic.201900311, 2019, 17, 2312-2317, 2019.05, Extraction of M elements from MAX phases results in “AX” compounds in contrast to the well-defined two-dimensional (2D) materials known as MXene, which are prepared by the selective etching of A elements. Despite the extensive studies on MXene from both experimental and computational aspects, the nature of the AX compounds still remains elusive, because the electrochemical etching of M atoms from MAX significantly spoils the crystal structure, predominantly resulting in amorphous AX products. Here, we demonstrate the characterization of an S/C complex prepared by the electrochemical etching of Ti
SC. The spark plasma sintering (SPS) technique affords a well-sintered Ti
SC disk with high purity, which can be directly utilized as a binder-free Ti
SC electrode. It is found that the electrochemically extracted Ti elements in NH
F electrolyte are partially crystallized into the monoclinic titanium oxynitride, TiO
. The formed amorphous S/C compound is classified into three components: acetone-soluble volatiles including elemental sulfur, acetone-insoluble volatiles, and non-volatile species carbonizable into S-doped carbon..
5. He Wang, Joji Hasegawa, Yuto Akiyama, Takahisa Yamamoto, Atsushi Inoishi, Hirofumi Akamatsu, Miki Inada, Tatsumi Ishihara, Katsuro Hayashi, A highly conductive Na
ceramic sheet prepared by tape-casting method, Electrochimica Acta, 10.1016/j.electacta.2019.03.057, 305, 197-203, 2019.05, Ceramic sheets of Na
(NVP) with NASICON-related structure have been prepared by tape-casting method. The addition of 60Na
glass to NVP is demonstrated to enhance markedly the density of the sintered NVP sheet and its electrical conductivity. The best densified NVP sheet with a thickness of a few tens of μm is obtained by sintering tape-casted NVP added with 5 wt% glass at 920 °C, which exhibits a total conductivity of 2.9 × 10
S cm
at room temperature. A Pt | NVP sheet | Pt cell works as a tiny solid-state battery with a cell potential of 1.7 V, in which NVP acts as both cathode and anode active materials via redox reactions of V
and V
as well as a Na
ion conducting electrolyte between the two electrode layers..
6. Joji Hasegawa, Moeko Tanaka, Junie Jhon M. Vequizo, Akira Yamakata, Hajime Hojo, Makoto Kobayashi, Masato Kakihana, Miki Inada, Hirofumi Akamatsu, Katsuro Hayashi, Sodium titanium oxide bronze nanoparticles synthesized via concurrent reduction and Na+-doping into TiO2(B), Nanoscale, 10.1039/c8nr08372j, 11, 3, 1442-1450, 2019.01, A mixed valence compound, sodium titanium oxide bronze (NaxTiO2-B), combines intriguing properties of high electric conductivity and good chemical stability together with a unique one-dimensional tunnel crystal structure available for cation storage. However, this compound has not been studied for a long period because of the strongly reductive condition at high temperature required for its preparation, which limits the morphological control such as the preparation of nanocrystals. For the first time in this paper, the topotactic synthesis of nano-sized NaxTiO2-B with high specific surface area (>130 m2g-1) from TiO2(B) nanoparticles has been demonstrated. The reaction of metastable TiO2(B) with NaBH4 allows carrier electrons to be doped simultaneously with incorporation of Na+ ions into the interstitial sites of the host Ti-O lattice at relatively low temperature. An electrochemical investigation of Li+- and Na+-ion storage behaviors suggests that the incorporated Na+ ions are mainly placed in the 6-fold coordination sites of bronze. In addition, optical measurements including time-resolved transient spectroscopy revealed that the doped electrons in the NaxTiO2-B nanoparticles are predominantly in the Ti3+ state and behave as a small polaron. The pelletized NaxTiO2-B nanoparticles shows a good electronic conductivity of 1.4 × 10-2 S cm-1 at 30 °C with an activation energy of 0.17 eV, which is attributable to the thermal barrier for the polaron hopping..
7. He Wang, Keisuke Okubo, Miki inada, George Hasegawa, Naoya Enomoto, Katsuro Hayashi, Low temperature-densified NASICON-based ceramics promoted by Na2O-Nb2O5-P2O5 glass additive and spark plasma sintering, Solid State lonics,Volume 322, 54-60 (2018), DOI: 10.1016/j.ssi.2018.04.025, 2018.09.
8. Keisuke Okubo, He Wang, Katsuro Hayashi, Miki Inada, Naoya Enomoto, George Hasegawa, Takashi Osawa, Hitoshi Takamura, A dense NASICON sheet prepared by tape-casting and low temperature sintering, Electrochimica Acta,Volume 278, 10, 176-181 (2018), DOI: 10.1016/j.electacta.2018.05.020, 2018.07.
9. Kenta Hongo, Sinji Kurata, Apichai Jomphoak, Miki Inada, Katsuro Hayashi and Ryo Maezono, Stabilization Mechanism of the Tetragonal Structure in a Hydrothermally Synthesized BaTiO3 Nanocrystal, Inorg. Chem, 57 (9), 5413-5419 (2018), DOI: 10.1021/acs.inorgchem.8b00381, 2018.03.
10. Naoya Enomoto, Shingo Hirata, Miki Inada, Katsuro Hayashi, Crystallization behavior of iron-based amorphous nanoparticles prepared sonochemically, Ultrasonics Sonochemistry, Volume 35, B, 563-568 (2017), DOI: 10.1016/j.ultsonch.2016.04.033, 2017.03.
11. Miki Inada, Naoya Enomoto, Junichi Hojo, Katsuro Hayashi, Structural analysis and capacitive properties of carbon spheres prepared by hydrothermal carbonization, Advanced Powder Technology, Volume 28, 884-889 (2017), DOI: 10.1016/j.apt.2016.12.014, 2017.03.
12. M. Inada, N. Enomoto, K. Hayashi, J. Hojo, S. Komarneni, Facile synthesis of nanorods of tetragonal barium titanate using ethylene glycol, Ceramics International, Volume 41, Issue 4, May 2015, Pages 5581–5587, doi:10.1016/j.ceramint.2014.12.137, 2015.05.
13. H. Tong, N. Enomoto, M. Inada, Y. Tanaka, J. Hojo, Synthesis of mesoporous TiO2 spheres and aggregates by sol-gel method for dye-sensitized solar cells, Materials Letters, Volume 141, 15 February 2015, Pages 259-262, DOI: 10.1016/j.matlet.2014.11.080, 141, 15, 259-262, 2015.02.
14. K. Koganei, T. Oyama, M. Inada, N. Enomoto, K. Hayashi, C-axis oriented β″-alumina ceramics with anisotropic ionic conductivity prepared by spark plasma sintering , Solid State Ionics, Volume 267, 1 December 2014, Pages 22-26, DOI: 10.1016/j.ssi.2014.09.003, 2014.12.
15. J. Hojo, W. Yang, M. Inada, Y. Tanaka, N. Enomoto, Sintering condition and microstructure of translucent silicon nitride ceramics , Journal of the Japan Society of Powder and Powder Metallurgy, Vol. 61 (2014) No. 12 December pp. 575-581, DOI: 10.2497/jjspm.61.575, 2014.12.
16. H. Tong, D. Chu, K. Zuoa, Y.-P. Zeng, N. Enomoto, M. Inada, Y. Tanaka, J. Hojo, Effect of Ni doping on the structure and properties of In2O3 nanocrystals prepared under magnetic field, Ceramics International, Volume 40, Issue 7, Part A, August 2014, Pages 9121–9125, DOI: 10.1016/j.ceramint.2014.01.126, 2014.08.
17. H. Tong, N. Enomoto, M. Inada, Y. Tanaka, J. Hojo, Hydrothermal synthesis of mesoporous TiO2-SiO2 core-shell composites for dye-sensitized solar cells, Electrochimica Acta, Volume 130, 1 June 2014, Pages 329–334,, 2014.06.
18. M. Inada, N. Enomoto, J. Hojo, Fabrication and structural analysis of mesoporous silica-titania for environmental purification, Microporous and Mesoporous Materials 182 (2013) 173–177, 2013.12.
19. Wenwu Yang, Junichi Hojo, Naoya Enomoto, Yumi Tanaka, Miki Inada, Influence of Sintering Aid on the Translucency of Spark Plasma-Sintered Silicon Nitride Ceramics, Journal of the American Ceramic Society,Vol. 96, pp. 2556–2561 (2013), 2013.08.
20. W. YANG, J. HOJO, N. ENOMOTO, Y. TANAKA, M. INADA, Near Infrared Transmittance of Translucent Si3N4 Sintered Ceramics, Materials Letters, Vol.96, pp.155-157 (2013), 2013.02.
21. W. YANG, M. INADA, Y. TANAKA, N. ENOMOTO, J. HOJO, Fabrication of Translucent Silicon Nitride Ceramics with Various Sintering Aids, International Journal of Nanotechnology, Vol.10, No.1/2, pp.119-125 (2013), 2012.12.
22. J. HOJO, H. TONG, S. SHINTANI, M. INADA, Y. TANAKA, N. ENOMOTO, Photovoltaic Properties of TiO2-ZnO Composite Electrodes for Dye-Sensitized Solar Cells, Journal of the Japan Society of Powder and Powder Metallurgy, Vol. 59, No.11, pp.621-625 (2012), 2012.11.
23. H. TONG, M. INADA, Y. TANAKA, N. ENOMOTO, J. HOJO, Preparation of Nanocrystalline ZnO/TiO2 FIilm and Its Application to Dye-Sensitized Solar Cells, Functional Materials Letters, Vol.5, No.2, 1260006(5 pages) (2012), 2012.06.
24. W-W YANG, M. INADA, Y. TANAKA, N. ENOMOTO, J. HOJO, Effects of Sintering Conditions and Additives on Translucent Silicon Nitride Ceramics, Materials Science Forum , Vol.274, pp.282-286 (2012), 2012.01.
25. H. TONG, M. INADA, Y. TANAKA, N. ENOMOTO, J. HOJO, Dye Sensitized Solar Cells Based on ZnO Nanorod/TiO2 Nanoparticle Composite Films, Materials Science Forum, Vol.274, pp.397-403 (2012), 2012.01.
26. N. Enomoto, T. Miyajima, M. Inada, Y.Tanaka, J. Hojo, K. Tanaka, Sono/Photo Synergy Effect Using TiO2-coated Fibers and 2.4 MHz Ultrasound, Proceedings of The 20th Annual Meeting of the Japan Society of Sonochemistry & The International Workshop on Advanced Sonochemistry, pp.45-46 (2011), 2011.11.
27. Miki INADA, Kazunori IWAMOTO, Naoya ENOMOTO and Junichi HOJO, Synthesis and photocatalytic activity of small brookite particles by self-hydrolysis of TiOCl2, Journal of the Ceramic Society of Japan, Vol. 119 (2011) , No. 1390 (June) pp.451-455, 2011.06.
28. M. Inada, K. Mizue, N. Enomoto, J. Hojo, Thermal Stability of Rutile TiO2 with High Specific Surface Area Synthesized by Self-Hydrolysis Process, Science of Advanced Materials, Vol.2, No.1, pp.102-106 (2010), 2010.03.
29. M. Inada, N. Enomoto, J. Hojo, Synthesis and Photocatalytic Activity of Mesoporous SiO2-TiO2, Research on Chemical Intermediates, Vol.36, No.1, 115-120 (2010), 2010.01.
30. K. Matsumoto, N. Saito, T. Mitate, J. Hojo, M. Inada, H. Haneda, Surface Polarity Determination of ZnO Spherical Particles Synthesized via Solvothermal Route, Crystal Growth & Design, Vol.9, No.12, pp.5014-5016, (2009), 2009.12.
31. N. ENOMOTO, R. NAMBA, M. KURAKAZU, M. INADA, J. HOJO, Sonoelectrochemical Processing of Nanostructured Titania, Proceeding of the 26th International Korea-Japan Seminar on Ceramics, つくば市, pp. 269-270 (2009), 2009.11.
32. M. Inada, K. Mizue, N. Enomoto, J. Hojo, Synthesis of Rutile TiO2 with High Specific Surface Area by Self-hydrolysis of TiOCl2 in the Presence of SDS, Journal of the Ceramic Society of Japan, Vol.117, No.1367, pp.819-822 (2009), 2009.07.
33. N. Enomoto, M. Kurakazu, M. Inada, K. Kamada, J. Hojo, W-I LEE, Effect of Ultrasonication on Anodic Oxidation of Titanium, Journal of the Ceramic Society of Japan, Vol.117, No.1363, pp.369-372 (2009), 2009.03.
34. K. MIZUE, M. INADA, N. ENOMOTO, J. HOJO, Synthesis of TiO2 Particles by Self-Hydrolysis Process under the Existence of Additives, Proceeding of the 25th Korea-Japan International Seminar on Ceramics, Gangneung, Korea, pp. 170-173 (2008), 2008.11.
35. M. Inada, A. Nishinosono, K. Kamada, N. Enomoto, J. Hojo, Microwave-assisted Sol-gel Process for Production of Spherical Mesoporous Silica Materials, Journal of Materials Science, Vol.43, No.7, pp.2362-2366 (2008), 2008.07.
36. M. Inada, J. Hojo, Microwave Processing for Fly-Ash Zeolite Production, Proceedings of International Symposium on EcoTopia Science 2007, ISETS07, (2007), 2007.11.
37. K. Kamada, K. Higashikawa, M. Inada, N. Enomoto, J. Hojo, Photoassisted Anodic Electrodeposition of Ceria Thin Films, The Journal of Physical Chemistry C, Vol.111, No.39, pp.14508-14513 (2007), 2007.10.
38. K. Kamada, M. Tokutomi, M. Inada, N. Enomoto, J. Hojo, Solid Electrochemical Micromachining Using a Tungsten Microlelectrode Coated with a Polymer Electrolyte, Journal of the Ceramic Society of Japan, Vol.115, No.10, pp.672-677 (2007), 2007.10.
39. M. Inada, K. Kamada, N. Enomoto, J. Hojo, Microwave Effect for Synthesis of TiO2 Particles by Self-hydrolysis of TiOCl2, Journal of the Ceramic Society of Japan, Vol.114, No.1334, pp.814-818 (2006), 2006.10.
40. M. Inada, H. Tsujimoto, Y. Eguchi, N. Enomoto, J. Hojo, Microwave-assisted Zeolite Synthesis from Coal Fly Ash in Hydrothermal Process, Fuel, Vol. 84, No. 12-13, pp.1482-1486 (2005), 2005.09.
41. M. Inada, Y. Eguchi, N. Enomoto, J. Hojo, Synthesis of Zeolite from Coal Fly Ashes with Different Silica-alumina Composition, Fuel, Vol.84, No.2-3, pp.299-304 (2005), 2005.01.
42. A. Nishinosono, M. Inada, K. Kamada, N. Enomoto, J. Hojo, Synthesis of Silica-Titania Nanoporous Materials with Modified Titanium Alkoxide, Proceeding of the 1st Kyushu-Busan Joint Symposium on Advanced Ceramics, Kitakyushu, Japan, pp.28-29, December, 2004, 2004.12.
43. M. Inada, N. Enomoto, J. Hojo, SYNTHESIS OF TiO2 PARTICLES BY SELF-HYDROLYSIS OF TiOCl2 USING DOMESTIC MICROWAVE, Proceedings of Austceram & The 3rd International Conference on Advanced Materials Processing (CD), pp.257-259, 2004, 2004.12.
44. M. Inada, Y. Eguchi, M. Uehara, N. Enomoto, J. Hojo, Mechanism and Morphological Change in Zeolite Formation from Coal Fly Ash, Transactions of the Materials Research Society of Japan, Vol.29, No.5, pp.2363-2366 (2004), 2004.12.
45. J. Hojo, H. Tsujimoto, M. Inada, Y. Eguchi, N. Enomoto, Zeolite Synthesis from Coal Fly Ash: Effect of Microwave Irradiation on the Hydrothermal Process, Proceeding of the 21st International Korea-Japan Seminar on Ceramics, B6, Gwangju, Korea, pp.459-463 (2004), 2004.11.
46. M. Inada, Y. Eguchi, M. Uehara, N. Enomoto and J. Hojo, Zeolite Synthesis from Coal Fly Ash: Formation Mechanism of Zeolite, Proc.19th Int'l Korea-Japan Seminar on Ceram.,pp.70-74 (2002), 2002.11.
47. M. Inada, Y. Eguchi, M. Uehara, N. Enomoto and J. Hojo, Zeolite Synthsis from Coal Fly Ash by Compositional Arrangement, Proc.5th int'l. Conf. Solvo-Thermal Reaction, pp.281-285 (2002), 2002.08.
48. J. Hojo, M. Inada, Y. Eguchi, M. Uehara and N. Enomoto, Synthsis and Formation Mechanism of Zeolite from Coal Fly Ash, Proc.5th int'l. Conf. Solvo-Thermal Reaction, pp.85-89 (2002), 2002.08.
49. N. Enomoto, M. Inada, Y. Eguchi, M. Uehara and J.Hojo, Microwave Syntesis of Zeolite from Coal Fly Ash and the Way to Scale Up, Tras. Mater. Res. Soc. Jpn, Vol.26, No.4, pp.1197-1200 (2001), 2001.12.
50. M. Inada, Y. Eguchi, M. Uehara, N. Enomoto and J. Hojo, Zeolite Syntesis from Coal Fly Ash: Influence of Silica-Alumina Composition, Proc. 18th Intl. Korea-Japan Seminar on Ceram., pp.552-556 (2001), 2001.11.
51. J. Hojo, T. Moriyama, M. Inada, Y. Eguchi, M. Uehara and N. Enomoto, Recycling of Incineration Residue of Municipal Refuse and Coal Fly Ash, Proc. 4th Intl. Conf. Mater, Eng. Resources (I), pp.147-149(2001), 2001.10.
52. M. Inada, Y. Eguchi, M. Uehara, N. Enomoto, J. Hojo, Zeolite Synthesis from Coal Fly Ash: Influence of Fly Ash Source and Synthesis Condition, Proc. 17th Int'l Korea-Japan Seminar on Ceram., pp.212-216 (2000), 2000.11.