1. Innovative Centre for Flexible Devices School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore
2. Department of Chemistry Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
3. Department of Chemistry University of Washington Seattle Washington 98195 USA
4. Department of Chemistry Seoul National University Seoul 08826 South Korea
5. Department of Chemistry Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM) City University of Hong Kong Hong Kong China
6. Shenzhen Research Institute City University of Hong Kong Shenzhen 518057 China