1. Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031, P. R. China
2. Sichuan Vanov New Material Co., Ltd., Qingshen
County, Chengdu, Sichuan 620400 P. R. China
3. School of Chemistry, Southwest Jiaotong University, Chengdu, Sichuan 610031, P. R. China