1. Anhui Province Industrial Generic Technology Research Center for Alumics Materials, School of Physics and Electronic Information, Huaibei Normal University, Huaibei, Anhui 235000, China
2. Key Laboratory for Special Functional Materials of Ministry of Education, and School of Materials Science and Engineering, Henan University, Kaifeng 475004, China
3. School of Materials Science and Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China