1. Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China
2. Materials Chemistry and Nanochemistry Research Group, Solar Fuels Cluster, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
3. School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
4. Department of Materials Science and Engineering, University of Toronto, Toronto, Ontario M5S 3E4, Canada
5. Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China
6. Ontario Centre for the Characterization of Advanced Materials, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada