1. College of Electronics and Information Science; Fujian Jiangxia University; Fuzhou 350108 P. R. China
2. Organic Optoelectronics Engineering Research Center of Fujian's Universities; Fujian Jiangxia University; Fuzhou 350108 PR China
3. State Key Laboratory of Structural Chemistry; Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences; Fuzhou 350002 P. R. China