Deng Jiawei, Li Wenhao, Zeng Rui, Song Jiali, Tan Senke, Kan Lixuan, Qin Zhao, Zhao Yan, Liu Feng, Sun Yanming
Hangzhou International Innovation Institute, Beihang University, Hangzhou, 311115, P. R. China.
School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, In situ Center for Physical Science, and Center of Hydrogen Science, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China.
Adv Mater. 2025 Jun;37(24):e2501243. doi: 10.1002/adma.202501243. Epub 2025 Apr 7.
For spontaneously crystallized organic photovoltaic materials, morphology optimization remains a challenge due to the disparity in crystallinity between the donor and acceptor components. Imperfections in the crystalline phases result in significant trap-assisted recombination, which emerges as a critical factor limiting the fill factor (FF) of organic solar cells (OSCs). Herein, a method is introduced for precise regulation of the acceptor crystallinity, utilizing a novel upper-layer acceptor processing solvent, trichloroethylene (TCE), to improve the state and vertical morphology of the active layer. The TCE solvent synergistically optimizes intermolecular interactions among acceptor molecules and balances the film-forming process, thereby increasing the proportion of transport phases and forming high-speed channels for electron transport, which subsequently reduces trap-assisted charge recombination. As a result, the photovoltaic efficiency of binary organic solar cells reaches 20.05%. More importantly, an unprecedented FF of 83.0% is obtained, representing the highest FF value for OSCs. This facile and effective approach offers a promising means for constructing efficient charge transport networks and fabricating high-efficiency and morphologically stable OSCs.
对于自发结晶的有机光伏材料，由于供体和受体组分之间结晶度的差异，形态优化仍然是一个挑战。结晶相中的缺陷会导致显著的陷阱辅助复合，这成为限制有机太阳能电池（OSC）填充因子（FF）的关键因素。在此，介绍一种精确调节受体结晶度的方法，利用新型上层受体加工溶剂三氯乙烯（TCE）来改善活性层的状态和垂直形态。TCE溶剂协同优化受体分子间的分子间相互作用并平衡成膜过程，从而增加传输相的比例并形成用于电子传输的高速通道，进而减少陷阱辅助电荷复合。结果，二元有机太阳能电池的光伏效率达到20.05%。更重要的是，获得了前所未有的83.0%的填充因子，这代表了OSC的最高FF值。这种简便有效的方法为构建高效电荷传输网络以及制造高效且形态稳定的OSC提供了一种有前景的手段。
