A Medium Bandgap D-A Copolymer Based on 4-Alkyl-3,5-difluorophenyl Substituted Quinoxaline Unit for High Performance Solar Cells
A Medium Bandgap D-A Copolymer Based on 4-Alkyl-3,5-difluorophenyl Substituted Quinoxaline Unit for High Performance Solar Cells
复制标题
用于高性能太阳能电池的基于4-烷基-3,5-二氟苯基取代喹喔啉单元的中带隙D-A共聚物
DOI：
10.1021/acs.macromol.8b00326
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发表时间：
2018
期刊：
影响因子：
5.5
通讯作者：
Zou Yingping
中科院分区：
文献类型：
--
作者：
Wang Tao;Lau Tsz Ki;Lu Xinhui;Yuan Jun;Feng Liuliu;Jiang Lihui;Deng Wei;Peng Hongjian;Li Yongfang;Zou Yingping
Development of high-performance donor–acceptor (D–A) copolymers has been indicated as a promising strategy to improve the power conversion efficiencies (PCEs) of organic solar cells (OSCs). In this work, a new medium bandgap conjugated D–A copolymer, HFAQx-T, based on 4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene (BDT-T) as donor unit, 4-alkyl-3,5-difluorophenyl substituted quinoxaline (HFAQx) as the acceptor unit, and thiophene as the spacer, was designed and synthesized. HFAQx-T is a well-compatible donor polymer; OSCs based on HFAQx-T exhibit excellent performance in both fullerene and fullerene-free based devices. The optimized conventional single junction bulk heterojunction (BHJ) OSCs of HFAQx-T:PC71BM showed a PCE of 9.2%, with an open circut voltage (Voc) of 0.9 V, a short circuit current (Jsc) of 14.0 mA cm–2, and a fill factor (FF) of 0.74. Also, when blended with 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)indanone)-5,5,11,11-tetrakis(4-hexylphenyl)dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]-dithiophene (ITIC), the HFAQx-T-based device exhibited a PCE of 9.6%. HFAQx-T is among a few D–A copolymers that can deliver >9% efficiency in both fullerene and fullerene-free solar cells. This work demonstrates that the 4-alkyl-3,5-difluorophenyl substituted quinoxaline (Qx) is a promising electron-accepting building block in constructing ideal D–A copolymers for OSCs.
