1. Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, P. R. China
2. National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou 510006, P. R. China
3. Key Laboratory of Bio-inspired Materials and Interfacial Science Technical, Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
4. School of Future Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, P. R. China