1. Department of Physics, Shanghai University, Shanghai 200444, China
2. Institute of Low-Dimensional Carbons and Device Physics, Shanghai University, Shanghai 200444, China
3. Materials Genome Institute (MGI), Shanghai University, Shanghai 200444, China
4. Department of Applied Chemistry, Meijo University, Nagoya 468-8502, Japan
5. Shanghai Key Laboratory of High Temperature Superconductors, Shanghai 200444, China