Recent advances in material design for organic solar cells (OSCs) are primarily focused on developing near-infrared non-fullerene acceptors, typically A-DA′D-A type acceptors (where A abbreviates an electron-withdrawing moiety and D, an electron-donor moiety), to achieve high external quantum efficiency while maintaining low voltage loss. However, the charge transport is still constrained by unfavorable molecular conformations, resulting in high energetic disorder and limiting the device performance. Here, a facile design strategy is reported by introducing the “wing” (alkyl chains) at the terminal of the DA′D central core of the A-DA′D-A type acceptor to achieve a favorable and ordered molecular orientation and therefore facilitate charge carrier transport. Benefitting from the reduced disorder, the electron mobilities could be significantly enhanced for the “wing”-containing molecules. By carefully changing the length of alkyl chains, the mobility of acceptor has been tuned to match with that of donor, leading to a minimized charge imbalance factor and a high fill factor (FF). We further provide useful design strategies for highly efficient OSCs with high FF.

有机太阳能电池（OSC）的材料设计的最新进展主要集中在开发近红外非富勒烯受体，通常是A-DA'DA型受体（其中A代表吸电子部分，D代表电子给体部分）。 ），以在保持低电压损耗的同时实现较高的外部量子效率。但是，电荷传输仍然受到不利的分子构象的限制，导致高能紊乱并限制了器件性能。在这里，通过在A-DA'DA型受体的DA'D中心核末端引入“翼”（烷基链）来实现一种良好的设计策略，以实现良好的有序分子取向，从而有利于电荷载流子运输。受益于减少的疾病，对于含有“翼”的分子，电子迁移率可以显着提高。通过仔细地改变烷基链的长度，调节了受体的迁移率以使其与供体的迁移率匹配，从而使电荷不平衡因子最小，填充因子（FF）高。我们还为高FF的高效OSC提供了有用的设计策略。