1. Key Laboratory of Environmental Friendly Function Materials Ministry of Education
2. College of Materials Science and Engineering
3. Huaqiao University
4. Xiamen 361021
5. P.R. China
6. Department of Chemistry
7. New York University
8. New York
9. USA
10. School of Materials Science and Engineering
11. Nanyang Technological University
12. Singapore 639798
13. Singapore
14. Key Laboratory of Flexible Electronics & Institute of Advanced Materials