College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.
Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
ACS Appl Mater Interfaces. 2017 Sep 20;9(37):31985-31992. doi: 10.1021/acsami.7b10995. Epub 2017 Sep 5.
A novel nonfullerene small molecular acceptor (BZIC) based on a ladder-type thieno[3,2-b]pyrrolo-fused pentacyclic benzotriazole core (dithieno[3,2-b]pyrrolobenzotriazole, BZTP) and end-capped with 1,1-dicyanomethylene-3-indanone (INCN) has been first reported in this work. Through introducing multifused benzotriazole and INCN, BZIC could maintain a high-lying lowest unoccupied molecular orbital (LUMO) energy level of -3.88 eV. Moreover, BZIC shows a low optical bandgap of 1.45 eV with broad and efficient absorption band from 600 to 850 nm due to increased π-π interactions by the covalently locking thiophene and benzotriazole units. A power conversion efficiency of 6.30% is delivered using BZIC as nonfullerene acceptor and our recently synthesized hexafluoroquinoxaline-based polymer HFQx-T as donor. This is the first time to synthesize mutifused benzotriazole-based molecules as nonfullerene electron acceptor up to date. The preliminary results demonstrate that the mutifused benzotriazole derivatives hold great potential for efficient photovoltaics.
本工作首次报道了一种基于梯型噻吩[3,2-b]吡咯并稠合五元环苯并三唑核（二噻吩[3,2-b]吡咯并苯并三唑，BZTP）和端基 1,1-二氰基乙烯基-3-茚满酮（INCN）的新型非富勒烯小分子受体（BZIC）。通过引入多稠合苯并三唑和 INCN，BZIC 可以保持高的最低未占据分子轨道（LUMO）能级-3.88 eV。此外，由于通过共键锁定噻吩和苯并三唑单元增加了 π-π 相互作用，BZIC 表现出低的光学带隙为 1.45 eV，具有从 600 到 850nm 的宽而有效的吸收带。使用 BZIC 作为非富勒烯受体和我们最近合成的基于六氟喹喔啉的聚合物 HFQx-T 作为供体，可获得 6.30%的功率转换效率。这是迄今为止首次将多稠合苯并三唑基分子作为非富勒烯电子受体进行合成。初步结果表明，多稠合苯并三唑衍生物在高效光伏方面具有巨大的潜力。
