1. Division of Chemistry and Chemical Engineering, California Institute of Technology, 210 Noyes Laboratory, Pasadena, California 91125, United States
2. Joint Center for Artificial Photosynthesis, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, United States
3. Beckman Institute, California Institute of Technology, Pasadena, California 91125, United States
4. Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, United States