AbstractAlthough fullerene derivatives such as [6,6]‐phenyl‐C61/C71‐butyric acid methyl ester (PC61BM/PC71BM) have dominated the the photoactive acceptor materials in bulk heterojunction organic solar cells (OSCs) for decades, they have several drawbacks such as weak absorption, limited structural tunability, prone to aggregation, and high costs of production. Constructing non‐fullerene small molecules with three‐dimensional (3D) molecular geometry is one of the strategies to replace fullerenes in OSCs. In this study, a 3D molecule, contorted hexa‐cata‐hexabenzocoronene tetra perylenediimide (HBC‐4‐PDI), was designed and synthesized. HBC‐4‐PDI shows a wide and strong light absorption in the whole UV‐vis region as well as suitable energy levels as an acceptor for OSCs. More importantly, the 3D construction effectively reduced the self‐aggregation of c‐HBC, leading to an appropriate scale phase separation of the blend film morphology in OSCs. A preliminary power conversion efficiency of 2.70 % with a champion open‐circuit voltage of 1.06 V was obtained in OSCs with HBC‐4‐PDI as the acceptor, which was the highest among the previously reported OSCs based on c‐HBC derivatives. The results indicated that HBC‐4‐PDI may serve as a good non‐fullerene acceptor for OSCs.
摘要虽然富勒烯衍生物(如[6,6]-苯基-C61/C71-丁酸甲酯(PC61BM/PC71BM))在体异质结有机太阳能电池(OSCs)的光活性受体材料中占据主导地位已有数十年之久,但它们也存在一些缺点,如吸收能力弱、结构可调性有限、容易聚集以及生产成本高。构建具有三维(3D)分子几何形状的非富勒烯小分子是替代 OSC 中富勒烯的策略之一。本研究设计并合成了一种三维分子,即扭曲的六方六苯并呋喃四过二亚胺(HBC-4-PDI)。HBC-4-PDI 在整个紫外-可见光区域都有广泛而强烈的光吸收,并有合适的能级作为 OSC 的受体。更重要的是,三维结构有效地减少了 c-HBC 的自聚集,从而在 OSCs 中实现了混合薄膜形态的适当尺度相分离。以 HBC-4-PDI 为受体的 OSC 初步获得了 2.70 % 的功率转换效率,冠军开路电压为 1.06 V,是之前报道的基于 c-HBC 衍生物的 OSC 中最高的。结果表明,HBC-4-PDI 可作为一种良好的非富勒烯受体用于 OSCs。