Kyushu University Academic Staff Educational and Research Activities Database
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Kazunari SASAKI Last modified date:2017.05.30

Professor / Hydrogen Utilization Processes
Department of Mechanical Engineering
Faculty of Engineering


Graduate School
Undergraduate School
Other Organization
Administration Post
Vice President
Director of International Research Center for Hydrogen Energy
Director of Next-Generation Fuel Cell Research Center


E-Mail
Homepage
http://www.mech.kyushu-u.ac.jp/~hup/english_top.html
Homepage of Prof. Kazunari SASAKI`s Laboratory .
http://h2.kyushu-u.ac.jp/english/index.html
Homepage of International Research Center for Hydrogen Energy .
Phone
092-802-3143
Fax
092-802-3223
Academic Degree
Dr. sc. techn. ETH
Field of Specialization
Fuel cell science and engineering, Hydrogen technology, Inorganic materials chemistry, Electrochemistry
Outline Activities
In the research group of Dr. Kazunari Sasaki, we focus on the R&D of fuel cell materials. Two major activities, on polymer electrolyte fuel cells (PEFC) and on solid oxide fuel cells (SOFC), are both supported by several research fundings, including national R&D project of SOFCs and PEFCs.

In our reserach group, we have various facilities including 30 evaluation systems of fuel cell electrchemical performance/properties (with Solartron impedance analyzers, Potentiostat/Galvanostat, CVs, multimeters), microscopes (High-resolution FESEM-EDX-STEM, SEM-EDX, AFM, STM, KFM), materials evaluation apparatus (XRD, XPS, BET, TG-DTA, TG-MS etc.), several gas chromatographs and GC-MS, as well as preparation apparatus for electrode catalysts and fuel cells. Thus our graduate students and research staffs can prepare FC-related materials and fuel cells and can analyze their performanece by themselves.

(1) Nano-structured Electrode Catalysts for PEFCs

Polymer electrolyte fuel cells (PEFCs) are promising energy systems with several advantages including high energy density, low-temperature operation, short start-up time etc., so that automobile, portable, as well as stationary applications are of technological interest. However, in the state-of-the-art cells, a large amount of noble metals should be used, leading to too high cost of fuel cell systems. A higher performance of electrode catalysts using less amount of noble metals, especially platinum, is essential, and this is one of the most relevant technological tasks in PEFC research and development.

In this research period, we focus on carbon support materials and oxide-based additives for electrode catalysts. Various types of carbon materials were applied and the influence of carbon nanostructure on electrochemical properties was analyzed to realize higher power generation characteristics and a reduction of noble metal loading of the electrode catalysts. Downsizing of electrode catalysts, Pt, was also carried out. We have succeeded, via colloidal processes, to prepare Pt nanoparticles with a crystallite size of ca. 3 nm. Effect of nanostructuring on electrochemical properties are also analyzed to establish materials design strategies of PEFC/DMFC electrode catalysts.

(2) Multi-Fuel Capable SOFCs

In our institution, we systematically characterize electrochemical performance, relevant transport properties of ceramic materials, the interactions between the fuel cell components and the fuel gas species, and equilibria in fuel gases. We wish to contribute to solid oxide fuel cells (SOFC) development and commercialization based on our fundamental research activities, e.g. by establishing optimum operational conditions of fuel cells, proposing alternative materials, and analyzing electrochemical reaction phenomena. We have focused on power generation characteristics of SOFCs operated with various kinds of fuel gases (including lower and higher hydrocarbons, alcohols, biogases, coal gases, GTL fuels, and fuels with various impurities), as one of the most advantageous features of SOFCs is their flexibility for fuel selections. Based on these advantages, we may realize e.g. zero-emission renewable energy systems with SOFCs. We have also developed sulfur-tolerant SOFCs with chemically modified fuel electrodes.
Research
Research Interests
  • Electrode materials for SOFCs
    keyword : Fuel cells, SOFC, Electrode materials, durability, poisoning
    1989.09.
  • Advanced Electrocatalysts for Polymer Electrolyte Fuel Cells
    keyword : Fuel Cells, PEFC, Electrocatalyst, Catalyst support materials, Carbon materials, Oxide electronic conductors
    1999.10.
  • Alternative Electrolyte Materials for Fuel Cell Applications
    keyword : Hydrogen Energy, Fuel Cells, Solid State Ionics
    1995.04.
  • Fuel Cell Materials Design by Nanostructuring
    keyword : Colloidal processes, Nano-size effects, Interfacial effects
    1995.04.
  • Defect Chemistry of Functional Ceramics
    keyword : Defect chemistry,Chemical Thermodynamics, Electrical conductors
    1995.04.
Current and Past Project
  • SOFCs are the most flexible fuel cells with respect to fuel selection. However, various impurities in practical fuels and/or from SOFC system components can cause poisoning of fuel electrodes and thus degradation of electrochemical performance. Impurity tolerance of SOFCs has been analyzed by using various impurity-containing gases with respect to operational conditions to understand poisoning mechanisms and to improve long-term durability of SOFC systems.
  • Higher performance and long-term durability of electrocatalysts are essential for polymer electrolyte fuel cells (PEFCs), where electrocatalyst support materials act as a very important role. In this study, as alternatives to conventional carbon black catalyst support, semiconducting oxides and carbon nanofibers have been applied. In-situ colloidal impregnation enables to prepare highly-dispersed Pt catalysts on such support materials. Principles for electrocatalyst design using alternative catalyst supports are discussed.
Academic Activities
Papers
1. Y. Kawasoe, S. Tanaka, T. Kuroki, H. Kusaba, K. Ito, Y. Teraoka, and K. Sasaki, Preparation and Electrochemical Activities of Pt–Ti Alloy PEFC Electrocatalysts, J. Electrochem. Soc., 154[9] B969-B975 (2007), 2007.07.
2. K. Sasaki, K. Susuki, A. Iyoshi, M. Uchimura, N. Imamura, H. Kusaba, Y. Teraoka, H. Fuchino, K. Tsujimoto, Y. Uchida, N. Jingo, H2S Poisoning of Solid Oxide Fuel Cells, J. Electrochem. Soc., Vol.153, No.11, A2023-A2029, 2006.11.
3. Y. Shiratori, Y. Teraoka, K. Sasaki, Ni1-x-yMgxAlyO-ScSZ anodes for solid oxide fuel cells, Solid State Ionics, Vol.177, No.15-16, 1371-1380, 2006.06.
4. K. Sasaki, K. Watanabe, K. Shiosaki, K. Susuki, and Y. Teraoka, Multi-fuel Capability of Solid Oxide Fuel Cells, JOURNAL OF ELECTROCERAMICS, 13, 1-3, 13 (1-3): 669-675 2004, 2004.11.
5. K. Sasaki, K. Shinya, S. Tanaka, Y. Kawazoe, T. Kuroki, K. Takata, H. Kusaba, and Y. Teraoka, Nanostructured PEFC Electrode Catalysts Prepared via In-situ Colloidal Impregnation, Mater. Res. Soc. Symp. Proc., 835, Vol. 835, 241-46 (2004)., 2004.11.
6. K. Sasaki, K. Watanabe, and Y. Teraoka, Direct-alcohol SOFCs: Current-voltage characteristics and fuel gas compositions, JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 151, 7, 151 (7): A965-A970 2004, 2004.07.
7. K. Sasaki and Y. Teraoka, Equilibria in fuel cell gases - II. The C-H-O ternary diagrams, JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 150, 7, 150 (7): A885-A888 JUL 2003, 2003.07.
8. K. Sasaki and Y. Teraoka, Equilibria in fuel cell gases - I. Equilibrium compositions and reforming conditions, JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 150, 7, 150 (7): A878-A884 JUL 2003, 2003.07.
9. K. Sasaki and J. Maier, Chemical surface exchange of oxygen on Y2O3-stabilized ZrO2, SOLID STATE IONICS, 161 (1-2): 145-154 JUL 2003, 2003.06.
10. K. Sasaki, Y. Hori, R. Kikuchi, K. Eguchi, A. Ueno, H. Takeuchi, M. Aizawa, K. Tsujimoto, H. Tajiri, H, Nishikawa, Y. Uchida, Current-voltage characteristics and impedance analysis of solid oxide fuel cells for mixed H-2 and CO gases, JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 149, 3, 149 (3): A227-A233 MAR 2002, 2002.03.
11. K. Sasaki, H. Kojo, Y. Hori, R. Kikuchi, K. Eguchi, Direct-alcohol/hydrocarbon SOFCs: Comparison of power generation characteristics for various fuels, ELECTROCHEMISTRY, 70, 1, 70 (1): 18-22 JAN 2002, 2002.01.
12. K. Sasaki and J. Maier, Re-analysis of defect equilibria and transport parameters in Y2O3-stabilized ZrO2 using EPR and optical relaxation, SOLID STATE IONICS, 134 (3-4): 303-321 OCT 2000, 2000.10.
13. K. Sasaki and J. Maier, In situ EPR studies of chemical diffusion in oxides, PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 2 (13): 3055-3061 2000, 2000.01.
14. K. Sasaki and J. Maier, Low-temperature defect chemistry of oxides. II. Analytical relations, JOURNAL OF APPLIED PHYSICS, 86, 10, 86 (10): 5434-5443 NOV 15 1999, 1999.11.
15. K. Sasaki and J. Maier, Low-temperature defect chemistry of oxides. I. General aspects and numerical calculations, JOURNAL OF APPLIED PHYSICS, 86, 10, 86 (10): 5422-5433 NOV 15 1999, 1999.11.
16. K. Sasaki and J. Maier, Low temperature defect chemistry of oxides, JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, 19 (6-7): 741-745 1999, 1999.06.
17. K. Sasaki, J. Claus, and J, Maier, Defect chemistry of oxides in partially frozen-in states: case studies for ZrO2(Y2O3), SrZrO3(Y2O3), and SrTiO3, SOLID STATE IONICS, 121 (1-4): 51-60 JUN 1999, 1999.06.
18. K. Sasaki and L. J. Gauckler, Microstructure-property relations of solid oxide fuel cells. Microstructural design of cathodes and current collectors, DENKI KAGAKU, 64 (6): 654-661 JUN 1996, 1996.06.
19. K. Sasaki, J. P. Wurth, R. Gschwend, M. Godickemeier, and L. J. Gauckler, Microstructure-property relations of solid oxide fuel cell cathodes and current collectors - Cathodic polarization and ohmic resistance, JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 143 (2): 530-543 FEB 1996, 1996.02.
20. L. J. Gauckler and K. Sasaki, Ionic and Electronic Conductivities of Homogeneous and Heterogeneous Materials in the System ZrO2-In2O3, SOLID STATE IONICS, 75: 203-210 JAN 1995, 1995.01.
21. K. Sasaki, H. P. Seifert, and L. J. Gauckler, Electronic Conductivity in In2O3 Solid Solutions with ZrO2, JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 141 (10): 2759-2768 OCT 1994, 1994.10.
22. K. Sasaki, P. Bohac, and L. J. Gauckler, Phase Equilibria in the System ZrO2-InO1.5, JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 76 (3): 689-698 MAR 1993, 1993.03.
23. T. Yano, K. Sasaki, T. Maruyama, T. Iseki, M. Ito, and S. Onose, A Step-heating Dilatometry Method to Measure the Change in Length due to Annealing of a SiC Temperature Monitor, NUCLEAR TECHNOLOGY, 93 (3): 412-415 MAR 1991, 1991.03.
24. K. Sasaki, T. Yano, T. Maruyama, and T. Iseki, Helium Release and Microstructure of Neutron-iraddiated SiC Ceramics, JOURNAL OF NUCLEAR MATERIALS, 179: 407-410 Part A, MAR-APR 1991, 1991.03.
Membership in Academic Society
  • Hydrogen Energy Systems Society of Japan
  • The Japan Society of Mechanical Engineers
Awards
  • Research on Degradation Mechanisms in Solid Oxide Fuel Cells
  • PEFC electrocatalysts supported on semiconducting oxides
Educational
Other Educational Activities
  • 2003.01.
  • 2002.01.