An aromatic lactam acceptor unit, thieno[3,2‐c]isoquinolin‐5(4H)‐one (TIQ), is developed. Compared with its analogues, dithieno[3,2‐b:2′,3′‐d]pyridin‐5(4H)‐one (DTP) and phenanthridin‐6(5H)‐one (PN), TIQ shows its advantage in constructing donor–acceptor (D–A) copolymers for efficient solar cells. TIQ‐based D–A copolymer PTIQ4TFBT delivers a power conversion efficiency (PCE) of 10.16% in polymer:fullerene solar cells, while those based on DTP and PN copolymers, PDTP4TFBT and PPN4TFBT, afford PCEs around 8.5%. The higher performance of PTIQ4TFBT:PC₇₁BM solar cells originates from enhanced short‐circuit current density (J_sc) and fill factor (FF), because of favorable morphology, less bimolecular recombination, and balanced charge transport in the active layer. Moreover, the performance for PTIQ4TFBT:PC₇₁BM solar cells is less sensitive to active layer thickness than PDTP4TFBT:PC₇₁BM and PPN4TFBT:PC₇₁BM solar cells. Over 8% PCEs can be obtained from PTIQ4TFBT:PC₇₁BM solar cells when the active layer thickness is over 500 nm.

中文翻译：

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Thieno [3,2-c]异喹啉-5（4H）-高效厚膜太阳能电池的一个构建基块

开发了芳香族内酰胺受体单元，噻吩并[3,2-c]异喹啉-5（4H）-1（TIQ）。TIQ与类似物dithieno [3,2-b：2'，3'-d] pyridin-5（4H）-one（DTP）和phenanthridin-6（5H）-one（PN）相比，TIQ在构建用于高效太阳能电池的供体-受体（DA）共聚物。基于TIQ的D–A共聚物PTIQ4TFBT在聚合物：富勒烯太阳能电池中的功率转换效率（PCE）为10.16％，而基于DTP和PN共聚物，PDTP4TFBT和PPN4TFBT的太阳能电池的PCE约为8.5％。PTIQ4TFBT：PC ₇₁ BM太阳能电池的更高性能源自增强的短路电流密度（J _sc）和填充因子（FF），因为其形态良好，双分子重组少，并且在有源层中的电荷传输平衡。此外，与PDTP4TFBT：PC ₇₁ BM和PPN4TFBT：PC ₇₁ BM太阳能电池相比，PTIQ4TFBT：PC ₇₁ BM太阳能电池的性能对有源层厚度的敏感性较低。当活性层厚度超过500 nm时，可以从PTIQ4TFBT：PC ₇₁ BM太阳能电池中获得超过8％的PCE 。