Synthesis and photovoltaic properties of fluorene-based copolymers with pendent donor–acceptor units
Two fluorene-based copolymers comprising identical pendent triphenylamine (donor)–benzothiadiazole (acceptor) unit on the C9 site of fluorene but different conjugated main chain structures were synthesized by Pd-catalyzed Stille reaction. The thermal, photophysical, electrochemical and photovoltaic properties are studied. The polymers have strong absorption in 300–650 nm. The bulk heterojunction solar cells were fabricated with the copolymers as the donors and PC71BM as the acceptor in a 1:3 weight ratio in the device configuration ITO/PEODT/copolymer:PC71BM (1:3)/LiF/Al. The power conversion efficiency of the device based on copolymer PF-BTh-DTS is 1.1 % with open-circuit voltage (V oc) 0.84 V under simulated AM 1.5 G solar irradiation (100 mW/cm2).
KeywordsHigh Occupied Molecular Orbital Lower Unoccupied Molecular Orbital Power Conversion Efficiency Intramolecular Charge Transfer Triphenylamine
This research was supported by the Natural Science Foundation of China (No. 50803021) and Exhibition Base of Production, Study and Research on New Polymer Materials and Postgraduate Students’ Innovation Training of Guangdong Higher Education Institutes (cgzhzd1007) and Combination Project of Guangdong Province and the Ministry Education of China (2011B090400423).
- 4.Z. He, C. Zhong, S. Su, M. Xu, H. Wu, Y. Cao, Nat. Photonics 6, 591 (2012)Google Scholar