Zhang Meiqi, Ma Yunlong, Zheng Qingdong
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, China.
University of Chinese Academy of Sciences, Beijing, China.
Front Chem. 2018 Sep 24;6:427. doi: 10.3389/fchem.2018.00427. eCollection 2018.
Compared to the traditional fullerene derivatives, non-fullerene acceptors show more tunable absorption bands as well as adjustable energy levels which are favorable for further PCE enhancement of organic solar cells. In order to enhance light-harvesting property of dithienonaphthalene (DTN)-based acceptors, we designed and synthesized two novel non-fullerene acceptors (DTNIF and DTNSF) based on a ladder-type DTN donor core flanked with two different acceptor units. In combination with a benchmark wide bandgap copolymer (PBDB-T), the best performance device based on DTNIF displayed a high PCE of 8.73% with a short-circuit current ( ) of 13.26 mA cm and a large fill factor (FF) of 72.77%. With a reduced bandgap of DTNSF, the corresponding best performance device showed an increased of 14.49 mA cm although only a moderate PCE of 7.15% was achieved. These findings offer a molecular design strategy to control the bandgap of DTN-based non-fullerene acceptors with improved light-harvesting.
与传统的富勒烯衍生物相比，非富勒烯受体显示出更可调节的吸收带以及可调节的能级，这有利于进一步提高有机太阳能电池的光电转换效率（PCE）。为了增强基于二噻吩并萘（DTN）的受体的光捕获性能，我们基于一个带有两个不同受体单元的梯型DTN供体核设计并合成了两种新型非富勒烯受体（DTNIF和DTNSF）。与一种基准宽带隙共聚物（PBDB-T）相结合，基于DTNIF的最佳性能器件显示出8.73%的高光电转换效率，短路电流（ ）为13.26 mA cm ，填充因子（FF）为72.77%。随着DTNSF带隙的减小，相应的最佳性能器件显示出短路电流增加到14.49 mA cm ，尽管仅实现了7.15%的中等光电转换效率。这些发现提供了一种分子设计策略，以控制基于DTN的非富勒烯受体的带隙并改善光捕获性能。
