Precisely controlling bulk heterojunction (BHJ)morphology through molecular design is one of the main long-standing challenges in developing high-performance organicsolar cells (OSCs). Herein, three small molecule acc...Precisely controlling bulk heterojunction (BHJ)morphology through molecular design is one of the main long-standing challenges in developing high-performance organicsolar cells (OSCs). Herein, three small molecule acceptors(SMAs) with different side chains (methyl, 2-ethylhexyl, and2-decyl tetradecyl on benzotriazole unit), namely R-M, R-EH,R-DTD, were designed and synthesized. Such side-chain en-gineering can effectively modulate the intermolecular inter-actions between acceptor/acceptor (A/A) and donor/A (D/A)molecules, thereby fine-tuning the bulk microstructures ofBHJ active layer systems. Compared with R-M and R-DTD,R-EH shows stronger A/A and D/A interactions with donorPM6, which delivers improved BHJ networks with bettermolecular ordering, enhancing charge transport and extrac-tion properties. Consequently, PM6:R-EH not only performs acompetitive device efficiency of over 18% but also exhibitsexcellent operation stability without obvious degradation be-haviors among the three systems. This study deepens the sy-nergistic effects of A/A and D/A interactions on BHJmorphology to achieve industrially viable OSCs with highdevice efficiency and stability.展开更多
基金financially supported by the National Natural Science Foundation of China (NSFC) (22279094 and 223B2904)the Fundamental Research Funds for the Central Universities+1 种基金supported by the Open Fund of the State Key Laboratory of Luminescent Materials and Devices (South China University of Technology, 2024-skllmd23)the support of the Opening Project of the Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China (2024A051)。
文摘Precisely controlling bulk heterojunction (BHJ)morphology through molecular design is one of the main long-standing challenges in developing high-performance organicsolar cells (OSCs). Herein, three small molecule acceptors(SMAs) with different side chains (methyl, 2-ethylhexyl, and2-decyl tetradecyl on benzotriazole unit), namely R-M, R-EH,R-DTD, were designed and synthesized. Such side-chain en-gineering can effectively modulate the intermolecular inter-actions between acceptor/acceptor (A/A) and donor/A (D/A)molecules, thereby fine-tuning the bulk microstructures ofBHJ active layer systems. Compared with R-M and R-DTD,R-EH shows stronger A/A and D/A interactions with donorPM6, which delivers improved BHJ networks with bettermolecular ordering, enhancing charge transport and extrac-tion properties. Consequently, PM6:R-EH not only performs acompetitive device efficiency of over 18% but also exhibitsexcellent operation stability without obvious degradation be-haviors among the three systems. This study deepens the sy-nergistic effects of A/A and D/A interactions on BHJmorphology to achieve industrially viable OSCs with highdevice efficiency and stability.
