1. Chemical Resources Laboratory, Tokyo Institute of Technology, R1-26, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan, Advanced Material Business Promotion Department, Osaka Gas Co., Ltd., 6-19-9 Torishima, Konohana-ku, Osaka 554-0051, Japan, and Nanodevice Research Laboratory, KRI Inc., Kyoto Research Park 134, Chudoji-minami-machi, Shimogo-ku, Kyoto 600-8813, Japan