1. Innovative Center for Flexible Devices (iFLEX); School of Materials Science and Engineering; Nanyang Technological University; 50 Nanyang Avenue Singapore 639798 Singapore
2. Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology; School of Pharmaceutical Sciences; Xiamen University; Xiamen 361102 P. R. China
3. Institute of Materials Research and Engineering; Agency for Science; Technology and Research (A*STAR); 2 Fusionopolis Way Singapore 138634 Singapore