1. Sustainable Energy Laboratory, Faculty of Materials Science and Chemistry, China University of Geosciences (Wuhan), 388 Lumo Road, Wuhan 430074, PR China
2. The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, No. 947 Heping Road, Wuhan 430081, PR China
3. Department of Physics, Penn State University, Berks Campus, Reading, Pennsylvania 19610-6009, United States