1. State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 China
2. Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing 100049 China
3. Dalian National Laboratory for Clean Energy Dalian 116023 China
4. State Key Laboratory of Environment-friendly Energy Materials Southwest University of Science and Technology Mianyang 621010 China
5. Department of Materials Science and Engineering Beijing Jiaotong University Beijing 100044 China
6. University of Saskatchewan Saskatoon Canada