1. Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and Technology Hebei University Baoding 071002 China
2. State Key Laboratory of Photovoltaic Materials & Technology Yingli Green Energy Holding Co., Ltd. Baoding 071051 China
3. R&D Department Das Solar Co., Ltd. No 43 Bailing South Road, Quzhou Green Industry Clustering Zone Quzhou Zhejiang 324022 China
4. Institute of Nanotechnology Karlsruhe Institute of Technology Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344 Karlsruhe Germany