南开大学阚斌团队报道了效率为20%的非卤化溶剂处理的，有机太阳能电池的3D二聚体受体异构效应。相关论文于2024年12月26日发表在《德国应用化学》杂志上。

可通过非卤化溶剂加工的有机光伏材料，对于有机太阳能电池（OSCs）的大面积制造至关重要。然而，具有足够溶解度和良好分子堆积的电子受体的可用性有限，这对实现高效的非卤化溶剂加工OSCs提出了挑战。

该文中，受三维二聚体受体CH8-4的启发，研究人员采用分子异构化策略，通过调整中心单元中氟（F）原子的位置来合成其异构体CH8-4A和CH8-4B。这些异构体之间不同的分子内氟硫非共价相互作用导致邻二甲苯（o-XY）溶液中分子预聚集能力（CH8-4B CH8-4 CH8-4A）的差异，这显著影响了成膜过程和由此产生的形态特征。

其中，CH8-4共混膜以适度的分子预聚集为特征，实现了最佳的双连续供体/受体相分离。因此，邻二甲苯处理的PM6:CH8-4装置实现了18.1%的功率转换效率（PCE），优于其他两种装置。通过将L8-BO-D作为客体受体，实现了基于CH8-4的三元器件20.0%的令人印象深刻的PCE，同时微型模块（13.5 cm²）的PCE较高接近16%。

研究结果表明了3D二聚体受体异构性，在提高环保OSCs性能方面的潜力。

附：英文原文

Title: Isomerism Effect of 3D Dimeric Acceptors for Non-halogenated Solvent-Processed Organic Solar Cells with 20% Efficiency

Author: Jia Wang, Peiran Wang, Tianqi Chen, Wenkai Zhao, Jiaying Wang, Baofa Lan, Wanying Feng, Hang Liu, Yongsheng Liu, Xiangjian Wan, Guankui Long, Bin Kan, Yongsheng Chen

Issue&Volume: 2024-12-26

Abstract: Organic photovoltaic materials that can be processed via non-halogenated solvents are crucial for the large-area manufacturing of organic solar cells (OSCs). However, the limited available of electron acceptors with adequate solubility and favorable molecular packing presents a challenge in achieving efficient non-halogenated solvent-processed OSCs. Herein, inspired by the three-dimensional dimeric acceptor CH8-4, we employed a molecular isomerization strategy to synthesize its isomers, CH8-4A and CH8-4B, by tuning the position of fluorine (F) atom in the central unit. The differing intramolecular fluorine-sulfur non-covalent interactions among these isomers led to differences in molecular pre-aggregation abilities (CH8-4B CH8-4 CH8-4A) in o-xylene (o-XY) solution, which significantly influence the film-forming process and the resultant morphological characteristics. Among these, the blend film of CH8-4, characterized by moderate molecular pre-aggregation, achieved optimal bi-continuous donor/acceptor phase separation. Consequently, the o-xylene processed PM6:CH8-4 device achieved a power conversion efficiency (PCE) of 18.1%, outperforming that of two other devices. By incorporating L8-BO-D as a guest acceptor, we attained an impressive PCE of 20.0% for the CH8-4-based ternary device, alongside a high PCE nearing 16% for the mini-module (13.5 cm2). Our findings underscore the potential of isomerism in 3D dimer acceptors to enhance the performance of eco-friendly OSCs.

DOI: 10.1002/anie.202423562

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202423562