1. Department of Applied Chemistry, School of Engineering, Tohoku University, 6-6-07 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
2. Research Center for Artificial Photosynthesis, Advanced Research Institute for Natural Science and Technology, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi, Osaka 558-8585, Japan
3. Organic Materials Research Laboratory, Tosoh Corporation, 4560, Kaisei-cho, Shunan 746-8501, Yamaguchi, Japan