Balancing Flexible Side Chains on 2D Conjugated Acceptors Enables High ‐Performance Organic Solar Cell

A series of nonfullerene acceptors, CH ─6F─Cn, with gradient substituent lengths of side chains are synthesized. The different chain lengths dramatically modulated intermolecular packing modes, crystallinity, and nanoscale morphology of the active layer. The highest PCE of 18.73% is achieved by OSCs employing D18:PM6:CH-6F-C8 as ligh t-harvesting materials. AbstractBalancing the rigid backbones and flexible side chains of light-harvesting materials is crucially important to reach optimized intermolecular packing, micromorphology, and thus photovoltaic performance of organic solar cells (OSCs). Herein, based on a distinctive CH-series acceptor platform with 2D conjugation extended backbones, a series of nonfullerene acceptors (CH-6F-Cn) are synthesized by delicately tuning the lengths of flexible side chains fromn-octyl ton-amyl. A systemic investigation has revealed that the variation of the side chain's length can not only modulate intermolecular packing modes and crystallinity but also dramatically improve the micromorphology of the active layer and eventual photovoltaic parameters of OSCs. Consequently, the highest PCE of 18.73% can be achieved by OSCs employingD18:PM6:CH-6F-C8 as light-harvesting materials.

Source: Small - March 28, 2024 Category: Nanotechnology Authors: Xingqi Bi, Shitong Li, Tengfei He, Hongbin Chen, Yu Li, Xinyuan Jia, Xiangjian Cao, Yaxiao Guo, Yang Yang, Wei Ma, Zhaoyang Yao, Bin Kan, Chenxi Li, Xiangjian Wan, Yongsheng Chen Tags: Research Article Source Type: research