1. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials; College of Materials Science and Engineering; Innovation Center for Textile Science and Technology; Donghua University; Shanghai 201620 P. R. China
2. Christopher Ingold Laboratory; Department of Chemistry; University College London; 20 Gordon Street London WC1H 0AJ UK
3. College of Chemistry; Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education); Nankai University; Tianjin 300071 P. R. China
4. Department of Materials Science and Engineering; College of Engineering; Peking University; Beijing 100871 P. R. China
5. College of Physics; Jilin University; Changchun 130012 P. R. China