1. Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, School of Materials Science and Engineering, Peking University, Beijing 100871
2. Luoyang Ship Material Research Institute, Xiamen 361101
3. Beijing National Laboratory of Molecular Science, Beijing Key Laboratory of Magnetoelectric Materials and Devices, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871
4. School of Polymer Science and Engineering, Center for Optoelectronic Materials and Devices, University of Southern Mississippi, Hattiesburg, MS 39406