Chao Pengjie, Chen Hui, Zhu Yulin, Lai Hanjian, Mo Daize, Zheng Nan, Chang Xiaoyong, Meng Hong, He Feng
Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, China.
School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen, 518055, China.
Adv Mater. 2020 Mar;32(10):e1907059. doi: 10.1002/adma.201907059. Epub 2020 Jan 29.
It is of great significance to develop efficient donor polymers during the rapid development of acceptor materials for nonfullerene bulk-heterojunction (BHJ) polymer solar cells. Herein, a new donor polymer, named PBTT-F, based on a strongly electron-deficient core (5,7-dibromo-2,3-bis(2-ethylhexyl)benzo[1,2-b:4,5-c']dithiophene-4,8-dione, TTDO), is developed through the design of cyclohexane-1,4-dione embedded into a thieno[3,4-b]thiophene (TT) unit. When blended with the acceptor Y6, the PBTT-F-based photovoltaic device exhibits an outstanding power conversion efficiency (PCE) of 16.1% with a very high fill factor (FF) of 77.1%. This polymer also shows high efficiency for a thick-film device, with a PCE of ≈14.2% being realized for an active layer thickness of 190 nm. In addition, the PBTT-F-based polymer solar cells also show good stability after storage for ≈700 h in a glove box, with a high PCE of ≈14.8%, which obviously shows that this kind of polymer is very promising for future commercial applications. This work provides a unique strategy for the molecular synthesis of donor polymers, and these results demonstrate that PBTT-F is a very promising donor polymer for use in polymer solar cells, providing an alternative choice for a variety of fullerene-free acceptor materials for the research community.
在非富勒烯体相异质结（BHJ）聚合物太阳能电池受体材料快速发展的过程中，开发高效的给体聚合物具有重要意义。在此，通过将环己烷-1,4-二酮嵌入噻吩并[3,4-b]噻吩（TT）单元的设计，开发了一种基于强缺电子核心（5,7-二溴-2,3-双（2-乙基己基）苯并[1,2-b:4,5-c']二噻吩-4,8-二酮，TTDO）的新型给体聚合物，命名为PBTT-F。当与受体Y6混合时，基于PBTT-F的光伏器件表现出16.1%的出色功率转换效率（PCE），填充因子（FF）高达77.1%。这种聚合物对于厚膜器件也显示出高效率，对于190 nm的有源层厚度，实现了约14.2%的PCE。此外，基于PBTT-F的聚合物太阳能电池在手套箱中储存约700 h后也表现出良好的稳定性，PCE高达约14.8%，这明显表明这种聚合物在未来商业应用中非常有前景。这项工作为给体聚合物的分子合成提供了独特的策略，这些结果表明PBTT-F是一种非常有前景的用于聚合物太阳能电池的给体聚合物，为研究界的各种无富勒烯受体材料提供了替代选择。
