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 Singapore 117543 Singapore
3. MOE Key Laboratory for Analytical Science of Food Safety and Biology Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety College of Chemistry Fuzhou University Fuzhou 350002 P. R. China
4. Department of Astronautical Science and Mechanics Harbin Institute of Technology Harbin 150001 P. R. China
5. CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
6. Department of Materials Science and Engineering National University of Singapore Singapore 117575 Singapore