1. Department of Electrical and Computer Engineering; University of Toronto; 10 King's College Road Toronto ON M5S 3G4 Canada
2. Department of Materials Science and Engineering; University of Toronto; Toronto, ON, Canada 184 College St Toronto ON M5S 3E4 Canada
3. Department of Mechanical and Industrial Engineering; University of Toronto; 5 King's College Road Toronto ON M5S 3G8 Canada
4. Bio-inspired Solar Energy Program; Canadian Institute for Advanced Research; Toronto Ontario M5G 1Z8 Canada
5. Department of Chemistry; University of California; Berkeley Berkeley CA 94720 USA
6. Department of Materials Science and Engineering; University of California; Berkeley Berkeley CA 94720 USA
7. Materials Sciences Division; Lawrence Berkeley National Laboratory; Berkeley CA 94720 USA
8. Chemical Sciences Division; Lawrence Berkeley National Laboratory; Berkeley CA 94720 USA. Kavli Energy Nanosciences Institute; University of California; Berkeley Berkeley CA 94720 USA