1. College of Chemistry Fuzhou University Fuzhou 350116 P. R. China
2. Fujian Science & Technology Innovation Laboratory for Optoelectronic Information Fuzhou 350116 P. R. China
3. Department of Material Science and Engineering City University of Hong Kong Hong Kong P. R. China
4. School of Information and Optoelectronic Science and Engineering South China Normal University Guangzhou 510006 P. R. China
5. Department of Chemistry University of Oxford Oxford OX1 3QZ UK
6. School of Life and Environmental Sciences Faculty of Science Engineering and Built Environment Deakin University Waurn Ponds VIC 3216 Australia