1. Guangxi University of Science and Technology, Liuzhou, Guangxi, 545006, P. R. China
2. Key Laboratory of Water Pollution Control Technology, Hunan Research Academy of Environmental Sciences, Changsha 410004, China
3. Department of Chemistry, Tsinghua University, Beijing 100084, China
4. Nanjing University, Nanjing, Jiangsu 21000, P. R. China
5. Center on Nanoenergy Research, School of Physical Science and Technology, Guangxi University, Nanning, Guangxi 530004, P. R. China