1. Department of Chemical & Biomolecular Engineering, National University of Singapore, Singapore 117585, Singapore
2. School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P. R. China
3. WPI-MANA, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
4. Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
5. Department of Physics, National University of Singapore, Singapore 117542, Singapore
6. Department of Biomedical Engineering, National University of Singapore, Singapore 117575, Singapore
7. Centre for Advanced 2D Materials, Graphene Research Centre, Singapore 117546, Singapore
8. NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117456, Singapore
9. Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore