1. Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
2. CAS Key Laboratory of Renewable Energy, Guangzhou 510640, P. R. China
3. Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, P. R. China
4. R&D Center of Xuyi Attapulgite Applied Technology, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Xuyi 211700, P. R. China
5. Nano Science and Technology Institute, University of Science and Technology of China, Suzhou 215123, P. R. China