1. College of Materials and New Energy, Chongqing University of Science and Technology. Chongqing 401331, China
2. State Key Laboratory of Environment-Friendly Energy Materials, School of Materials and Chemistry, Southwest University of Science and Technology, Mianyang 621010, China
3. Ecomaterials and Renewable Energy Research Center, School of Physics, Nanjing University, Nanjing 211102, China