1. College of Physics and Optoelectronics, Taiyuan University of Technology, Jinzhong, 030060, P. R. China
2. College of Environmental Science and Engineering, Taiyuan University of Technology, Jinzhong, 030600, P. R. China
3. Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization, Taiyuan University of Technology, Taiyuan, 030024, P. R. China