1. Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, P. R. China
2. University of Chinese Academy of Sciences, Beijing 100044, P. R. China
3. Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing 401331, P. R. China
4. Analytical and Testing Center, Chongqing University, Chongqing 401331, P. R. China
5. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, P. R. China