Owing to the simple synthesis and flexible chemical modifiability of unfused-ring non-fullerene acceptors (UF-NFAs), they have gained great research attraction for fabricating organic solar cells (OSCs). However, UF-NFA-based devices still underperform fused-ring non-fullerene acceptor-based devices. Herein, a series of UF-NFAs based on a fluorinated quinoxaline (Qx) building block functionalized with meta-positioned alkoxy chains, namely FQxOC8-H, FQxOC8-F, and FQxOC8-Cl, are synthesized. Density-functional theory (DFT) calculations demonstrated that all UF-NFAs exhibited good backbone coplanarity, owing to the S⋯N and H⋯F nonbonding interactions. The resulting UF-NFAs showed broad absorption ranged from 500 to 900 nm as well as deep highest occupied molecular orbital (HOMO) levels. FQxOC8-Cl exhibited more red-shifted and greater absorption coefficient owing to the stronger molecular stacking caused by chlorine atoms of the end groups. Moreover, PM6:FQxOC8-Cl-based blended film exhibited reduced charge recombination, higher carrier mobilities, and suitable phase-separation domains. Accordingly, OSCs based on FQxOC8-Cl yielded a superior power conversion efficiency (PCE) of 10.52%. In contrast, FQxOC8-H-based device afforded a lower efficiency of 6.13%. Our work indicates that combining the fluorinated Qx motif functionalized with meta-positioned alkoxy chains with electron-withdrawing end-groups showed great potential to construct efficient UF-NFAs.

由于非稠环非富勒烯受体（UF-NFA）的简单合成和灵活的化学修饰，它们在制造有机太阳能电池（OSC）方面获得了巨大的研究吸引力。然而，基于 UF-NFA 的器件的性能仍然低于基于稠合环非富勒烯受体的器件。本文中，一系列基于氟化喹喔啉 (Qx) 结构单元的 UF-NFA，通过间位烷氧基链进行功能化，即FQxOC8-H、FQxOC8-F和FQxOC8-Cl, 进行合成。密度泛函理论 (DFT) 计算表明，由于 S⋯N 和 H⋯F 非键相互作用，所有 UF-NFA 都表现出良好的主链共面性。由此产生的 UF-NFA 显示出 500 至 900 nm 范围内的广泛吸收以及深最高占据分子轨道 (HOMO) 水平。由于端基氯原子引起更强的分子堆积， FQxOC8-Cl表现出更多的红移和更大的吸收系数。此外，PM6: FQxOC8-Cl基共混膜表现出减少的电荷复合、更高的载流子迁移率和合适的相分离域。因此，基于FQxOC8-Cl 的OSC具有 10.52% 的优异功率转换效率 (PCE)。相比之下，FQxOC8-H基于器件的效率较低，为 6.13%。我们的工作表明，将具有吸电子端基的间位烷氧基链功能化的氟化 Qx 基序组合起来，显示出构建高效 UF-NFA 的巨大潜力。