1. Joint School of National University of Singapore and Tianjin University International Campus of Tianjin University Binhai New City Fuzhou 350207 P. R. China
2. Department of Chemistry National University of Singapore 3 Science Drive 3 Singapore 117543 Singapore
3. Department of Chemical and Biomolecular Engineering National University of Singapore Singapore 117585 Singapore
4. International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Shaanxi 710049 P. R. China
5. Nanoyang Group, Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage, School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China
6. Dunman High School 10 Tanjong Rhu Road Singapore 436895 Singapore
7. Department of Physics National University of Singapore 2 Science Drive 3 Singapore 117542 Singapore