1. Materials Research Laboratory, University of California; Santa Barbara California 93106
2. Department of Chemical Engineering; University of California; Santa Barbara California 93106
3. Department of Materials; University of California; Santa Barbara California 93106
4. Department of Materials Science and Engineering; University of Ioannina, University Campus; Ioannina 45110 Greece
5. Lawrence Berkeley National Laboratory; Joint Center for Artificial Photosynthesis; Berkeley California 94720