摘要
Sidechain engineering as an efficient and convenient strategy has been widely used to optimize molecular structure of photovoltaic materials for boosting power conversion efficiency(PCE)of organic solar cells(OSCs).Herein,a new Y-series acceptor named Y-Th Si with trialkylsilyl-substituted thiophene as conjugated sidechain is developed.Compared with its parental Y6 with multiple intermolecular interactions,Y-Th Si has a unitary molecular packing due to the additional steric hindrance from twodimensional(2D)-conjugated trialkylsilyl-thiophene.Therefore,Y-Th Si shows an obviously blue-shifted absorption with an onset of~850 nm but significantly up-shifted lowest unoccupied molecular orbital energy level.For the PM6:Y-Th Si pair,the spin-coating OSCs achieve a decent PCE of 14.56%with an impressively high photovoltage(V_(OC))of 0.936 V.Inspired by its high V_(OC)and narrow absorption,Y-Th Si is introduced into near-infrared absorbing binary PM6:BTP-eC9 host to construct ternary OSCs.Thanks to the complementary absorption,optimized morphology,and minimized energy loss properties,the PM6:BTP-e C9:Y-Th Si-based OSCs offer a higher PCE of 18.34%.Moreover,our developed strategy can overcome the commonly existed PCE drop when the blade-coating towards large-scale printing is used instead.Therefore,a comparable PCE of 18.34%is achieved,which is one of the best values for the blade-coating OSCs so far.
基金
supported by the National Natural Science Foundation of China(22209131,22005121,21875182,52173023)
the National Key Research and Development Program of China(2022YFE0132400)
the Key Scientific and Technological Innovation Team Project of Shaanxi Province(2020TD-002)
the 111 Project 2.0(BP0618008)。
