1. Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, Beijing 100044, China
2. Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong, China
3. Organic Optoelectronic Materials Laboratory, Department of Chemistry, College of Science, Korea University, Seoul 02841, South Korea
4. Center for Advanced Low-Dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
5. Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China