1. School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, P. R. China
2. Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150500, P. R. China
3. Department of Functional Materials, School of Materials Science and Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043, P. R. China
4. School of Mechanical Engineering, Chengdu University, Chengdu 610106, P. R. China