1. Chinese
Academy of Sciences Key Laboratory of Materials for Energy Conversion,
Department of Materials Science and Engineering, University of Science and Technology of China, Jinzhai Road 96, Hefei Anhui 230026, People’s Republic of China
2. Department
of Physics, Tamkang University, New Taipei City 25137, Taiwan
3. Materials
Science and Engineering Department, University of Ioannina, GR-451 10 Ioannina, Greece
4. Research Institute of Petroleum Exploration and Development-LangFang, Langfang Hebei 065000, People’s Republic of China