1. Institute of Materials Research and Engineering (IMRE)
2. A*STAR (Agency for Science, Technology and Research)
3. Singapore 117602
4. Republic of Singapore
5. Division of Nanomaterials and Chemistry
6. Hefei National Laboratory for Physical Sciences at Microscale
7. University of Science and Technology of China
8. Hefei 230026
9. P. R. China
10. Department of Chemistry