Volatile solid additive (SA) with diverse chemical structures has been proved to be an alternative to prepare high-efficient organic solar cells (OSCs). While, various organic photovoltaic materials raise challenges in selecting suitable SAs during the device optimization. Herein, based on the simple and commonly used thiophene unit, we proposed a perhalogenated 2,5-dichloro-3,4-diiodothiophene (SA-T5) as the SA for the device optimizations. As results, the capacity of SA-T5 in optimizing molecular packings of small-molecular acceptor L8-BO, dimeric acceptor DL8, and polymeric acceptor PY-DT based blend films has been demonstated. Their optimized morphologies assisted by SA-T5 contribute to the suppressed charge recombination and enhanced charge transportation, resulting in their improved short-circuit current density and fill factor, simultaneously. In comparsion with as-cast devices, SA-T5-treated devices showed significantly improved power conversion efficiencies (PCEs) of 18.8 % for PM6:L8-BO, 17.8 % for PM6:DL8, and 17.6 % for PM6:PY-DT, respectively. Furthermore, the potential of SA-T5 in obtaining high-performance ternary OSCs was also confirmed, for example, a 18.1 % efficiency was realized in PM6:DL8:L8-BO based device. To our knowledge, the performance of these SA-T5-treated devices reaches the best results of different acceptor-based OSCs. Importantly, this work provides a rare and successful case to develop versatile SAs for high-performance OSCs.

中文翻译：

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2,5-二氯-3,4-二碘噻吩作为高性能有机太阳能电池的多功能固体添加剂


具有多种化学结构的挥发性固体添加剂（SA）已被证明是制备高效有机太阳能电池（OSC）的替代品。与此同时，各种有机光伏材料给器件优化过程中选择合适的SA带来了挑战。在此，基于简单且常用的噻吩单元，我们提出了全卤代2,5-二氯-3,4-二碘噻吩（SA-T5）作为器件优化的SA。结果表明，SA-T5 优化基于小分子受体 L8-BO、二聚体受体 DL8 和聚合受体 PY-DT 的共混膜的分子堆积的能力已得到证实。 SA-T5 辅助下的优化形态有助于抑制电荷复合和增强电荷传输，同时提高短路电流密度和填充因子。与铸态器件相比，经过 SA-T5 处理的器件的功率转换效率 (PCE) 显着提高，PM6:L8-BO 为 18.8%，PM6:DL8 为 17.8%，PM6:PY-DT 为 17.6%。分别。此外，SA-T5在获得高性能三元OSC方面的潜力也得到了证实，例如，在基于PM6:DL8:L8-BO的器件中实现了18.1%的效率。据我们所知，这些经过 SA-T5 处理的器件的性能达到了不同基于受体的 OSC 的最佳结果。重要的是，这项工作为开发高性能 OSC 的多功能 SA 提供了一个罕见且成功的案例。