1. Department of Chemistry, Fudan University, Shanghai 200433, China
2. State Key Laboratory for Modification of Chemical Fiber and Polymer Materials, Key Lab of Science and Technology of Eco-Textile, Ministry of Education, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China
3. Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping 60174, Sweden
4. Department of Physics and Astronomy, Uppsala University Box 516, SE-75120 Uppsala, Sweden
5. State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China