In the past few years, compared with the rapid development of polymer solar cells (PSCs), the research progress of all-small-molecule organic solar cells (ASM-OSCs) lags far behind. Herein, two kinds of C-shaped SM donors named FBD-S3 and TBD-S4, bearing subtly tailorable asymmetric central core, are firstly reported. Both the two SMs show broad as well as matched absorption and energy level with classical acceptor Y6. The introduction of asymmetric core endows SM with Y6-similar bending skeleton and a unique network assembly in which the SM donor can easily interpenetrate into neighboring Y6 via strong intermolecular interaction and facile stacking direction. These features would hinder rapid aggregation and prevent to form large domains of single component in blends, resulting in an extraordinary power conversion efficiency of 15.10% in TBD-S4:Y6-based device, which is one of the highest values for ASM-OSCs. In addition, our comparative study demonstrates that although the donor material TBD-S4 exhibits reduced crystallinity, such a molecule matches better with acceptor Y6 and works more efficiently for ASM-OSCs. This work indicates that conformation tailorable by asymmetric central core is a novel and powerful method to design SM donor, which open a new avenue for highly efficient ASM-OSCs.

近年来，与聚合物太阳能电池（PSC）的快速发展相比，全小分子有机太阳能电池（ASM-OSC）的研究进展滞后。本文首次报道了两种C型SM供体，分别命名为FBD-S3和TBD-S4，它们具有可调节的不对称中心核。两种SM均显示出与经典受体Y6相同的宽泛以及匹配的吸收和能级。不对称核心的引入赋予SM具有类似Y6的弯曲骨架和独特的网络组件，其中SM供体可以通过强烈的分子间相互作用和容易的堆叠方向轻松地渗透到相邻的Y6中。这些功能将阻止快速聚集，并阻止在混合中形成单个成分的大区域，从而在TBD-S4中产生15.10％的非凡功率转换效率：基于Y6的设备，它是ASM-OSC的最大值之一。此外，我们的比较研究表明，尽管供体材料TBD-S4的结晶度降低，但这种分子与受体Y6的匹配更好，对ASM-OSC的作用更高。这项工作表明非对称中心核可定制的构象是设计SM供体的一种新颖而强大的方法，这为高效的ASM-OSC开辟了一条新途径。