1. Center for Molecular Systems and Organic Devices (CMSOD); Key Laboratory for Organic Electronics & Information Displays (KLOEID) and Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications; Nanjing 210003 P. R. China
2. Pillar of Engineering Product Development; Singapore University of Technology and Design; Singapore
3. Jiangsu-Singapore Joint Research Center for Organic/Bio- Electronics & Information Displays; Institute of Advanced Materials; Nanjing Tech University; Nanjing 211816 P. R. China