1. Center of Nanomaterials for Renewable Energy
2. State Key Laboratory of Electrical Insulation and Power Equipment
3. School of Electrical Engineering
4. Xi'an Jiaotong University
5. Xi'an 710049
6. Department of Environmental Science and Engineering
7. School of Energy and Power Engineering
8. China
9. State Key Laboratory of Crystal Materials
10. Shandong University
11. Jinan