1. Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy School of Materials & Energy Southwest University Chongqing 400715 P. R. China
2. Institute of Chemistry Henan Academy of Sciences Zhengzhou 450002 P. R. China
3. Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Department of Chemistry Wuhan University Wuhan 430072 P. R. China