1. State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
2. Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong
3. Guangdong Choicore Optoelectronics Co. Ltd., Heyuan 517003, China
4. Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China