1. Hebei Key Lab of Optic-electronic Information and Materials, National and Local Joint Engineering Laboratory of New Energy Photoelectric Devices, The College of Physics Science and Technology, Institute of Life Science and Green Development, Hebei University, Baoding, 071002, China
2. Department of Electronics and Optical Engineering, Army Engineering University, Shijiazhuang 050003, China
3. State Key Laboratory of Photovoltaic Materials & Technology, Yingli Solar, Baoding 071051, China