1. School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, PR China
2. Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
3. Hunan Province Key Laboratory of Applied Environmental Photocatalysis, Changsha University, Changsha, 410022, PR China
4. Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
5. Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Adyar, Chennai 600036, Tamil Nadu, India
6. School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, P.R. China