1. School
of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
2. Key
Laboratory for Organic Electronics and Information Displays (KLOEID)
and Institute of Advanced Materials (IAM), Jiangsu National Synergetic
Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications, 9 Wenyuan Road, Nanjing 210046, China
3. Key
Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced
Materials (IAM), Jiangsu National Synergistic Innovation Center for
Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, China
4. Laboratory
for Nanomaterials, National Center for Nanoscience and Technology, Beijing 100190, P. R. China