1. Division
of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
2. Joint
Center for Artificial Photosynthesis, California Institute of Technology, Pasadena, California 91125, United States
3. Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
4. Materials
Science Department, Darmstadt University of Technology, Petersenstrasse
32, 64287 Darmstadt, Germany
5. Kavli
Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, United States