He Keqiang, Kumar Pankaj, Yuan Yi, Zhang Zhifang, Li Xu, Liu Haitao, Wang Jinliang, Li Yuning
Department of Chemical Engineering and Waterloo Institute for Nanotechnology (WIN), University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.
Institute of Chemistry, Henan Academy of Sciences, 56 Hongzhuan Road, Jinshui District, Zhengzhou, Henan 450002A, China.
ACS Appl Mater Interfaces. 2021 Jun 9;13(22):26441-26450. doi: 10.1021/acsami.1c02442. Epub 2021 May 25.
Oxime-substituted thiophene (TO) is used as an acceptor (A) unit to copolymerize with the benzodithiophene (BDT) donor (D) unit to form a novel D-A polymer donor, PBDTTO, which has a low-lying highest occupied molecular orbital energy level () of -5.60 eV and a wide bandgap of 2.03 eV, forming complementary absorption and matching energy levels with the narrow bandgap nonfullerene acceptors. Organic solar cells using PBDTTO and Y6 as the donor and acceptor, respectively, exhibited a of 27.03 mA cm, a of 0.83 V, and a fill factor of 0.59, reaching a high power conversion efficiency of 13.29%. The unencapsulated devices show good long-term stability in ambient air. Compared with the acceptor monomers used in other high-performance BDT-based D-A polymer donors, which are synthesized tediously in low yields, the TO acceptor monomer can be conveniently synthesized in only two steps with a high overall yield of 70%. These results demonstrate that TO unit can be used as a promising acceptor unit for developing BDT-based D-A polymer donors at low cost while maintaining high photovoltaic performance.
肟取代的噻吩（TO）用作受体（A）单元，与苯并二噻吩（BDT）供体（D）单元共聚，形成一种新型的给体-受体（D-A）聚合物给体PBDTTO，其最高占据分子轨道能级（）较低，为-5.60 eV，带隙较宽，为2.03 eV，与窄带隙非富勒烯受体形成互补吸收和匹配能级。分别使用PBDTTO和Y6作为供体和受体的有机太阳能电池，其电流密度为27.03 mA cm，开路电压为0.83 V，填充因子为0.59，实现了13.29%的高功率转换效率。未封装的器件在环境空气中表现出良好的长期稳定性。与用于其他高性能基于BDT的D-A聚合物供体的受体单体相比，它们合成繁琐且产率低，而TO受体单体只需两步即可方便地合成，总产率高达70%。这些结果表明，TO单元可作为一种有前景的受体单元，用于低成本开发基于BDT的D-A聚合物供体，同时保持高光伏性能。
