Chlorination is a very effective technique to adjust molecular energy levels, absorption spectra and intermolecular π–π stacking of small-molecule acceptors (SMAs). On this basis, a new acceptor-donor-donor-acceptor (A-D-D-A)-type SMA IDT2-IC-4Cl with chlorinated end units was developed. Compared with the unchlorinated counterpart (IDT2-IC), the IDT2-IC-4Cl exhibited an efficient absorption ability in the range of 550–900 nm region. Moreover, the blend films of PBDB-T:IDT2-IC-4Cl exhibited better charge generation properties and more balanced charge mobilities as compared to those of PBDB-T:IDT2-IC blend films. Polymer solar cells (PSCs) based on PBDB-T:IDT2-IC-4Cl exhibited a power conversion efficiency (PCE) of 12.53% with a short-circuit current (J_sc) of 22.22 mA cm⁻² and a fill factor (FF) of 69.81, while the PBDB-T:IDT2-IC device yielded a PCE of 8.18% with a J_sc of 13.23 mA cm⁻² and a FF of 65.71. The results show that chlorination is an effective way to obtain high-performance SMAs.

氯化是一种非常有效的技术，可以调整分子能级、吸收光谱和小分子受体 (SMA) 的分子间 π-π 堆积。在此基础上，开发了一种新型的具有氯化末端单元的受体-供体-供体-受体（ADDA）型SMA IDT2-IC-4Cl。与未氯化的对应物（IDT2-IC）相比，IDT2-IC-4Cl 在 550-900 nm 范围内表现出有效的吸收能力。此外，与 PBDB-T:IDT2-IC 共混薄膜相比，PBDB-T:IDT2-IC-4Cl 共混薄膜表现出更好的电荷生成特性和更平衡的电荷迁移率。基于 PBDB-T:IDT2-IC-4Cl 的聚合物太阳能电池 (PSC) 的功率转换效率 (PCE) 为 12.53%，短路电流 ( J _sc ) 为 22.22 mA cm ^-2和填充因子 (FF) 为 69.81，而 PBDB-T:IDT2-IC 器件的 PCE 为 8.18%，J _sc为 13.23 mA cm ^-2，FF 为 65.71。结果表明，氯化是获得高性能SMAs的有效途径。