1. Innovation Research Center for Fuel Cells, The University of Electro-Communications, Chofugaoka, Chofu, Tokyo 182-8585, Japan
2. Japan Synchrotron Radiation Research Institute, Spring-8, Sayo, Hyogo 679-5198, Japan
3. Department of Chemistry, Graduate School of Science, Nagoya University, Chikusa, Nagoya, Aichi 464-8602, Japan
4. Department of Mathematical and Material Sciences, Faculty of Integrated Arts and Sciences, The University of Tokushima, Minamijosanjima, Tokushima 770-8502, Japan
5. Department of Engineering Science, Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofugaoka, Chofu, Tokyo 182-8585, Japan