1. Printable Electronics Research Centre, Suzhou Institute of Nanotech and Nanobionics, Chinese Academy of Sciences, No. 398 Ruoshui Road, Suzhou Industrial
Park, Suzhou 215123, P. R. China
2. International Research Laboratory of Information Display and Visualization, School of Electronic Science and Engineering, Southeast University, Nanjing 210096, P. R. China
3. Key Laboratory for the Physics and Chemistry of Nanodevices and Centre for Carbon-based Electronics, Department of Electronics, Peking University, Beijing 100871, P. R. China
4. MIIT Key Laboratory of Advanced Display Materials and Devices, Institute of Optoelectronics & Nanomaterials, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China