1. Institute of Chemistry & Biochemistry-Physical & Theoretical Chemistry; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
2. Department of Mechanical Engineering; Massachusetts Institute of Technology, 77; Massachusetts Ave., Cambridge, MA 02139 USA
3. Chemical Science and Engineering Division; Argonne National Laboratory, 9700; Cass Ave., Argonne, IL 60439 USA
4. Fuel Cell Nanomaterials Center; University of Yamanashi, 6-43; Miyamae-cho, Kofu, Yamanashi 400-0021 Japan