1. College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Jiangsu 215123, China.
2. Department of Materials Science and Engineering, and Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871, China.
3. The Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT), College of Engineering, Peking University, Beijing 100871, China.
4. Key Laboratory of Theory and Technology of Advanced Batteries Materials, College of Engineering, Peking University, Beijing 100871, China.
5. Department of Physics and Astronomy, California State University, Northridge, CA 91330, USA.
6. Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
7. Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China.