Tailoring small-molecule acceptors through asymmetric side-chain substitution for efficient organic solar cells  

通过不对称侧链取代调控小分子受体用于高效有机太阳能电池

作　　者：Lan Xie Dingding Qiu Xianghao Zeng Chung Hang Kwok Yan Wang Jia Yao Kan Ding Lu Chen Jicheng Yi Harald Ade Zhixiang Wei Wai-Yeung Wong He Yan Han Yu 谢兰;仇丁丁;曾祥淏;郭仲衡;王焱;姚嘉;丁堪;陈露;易际埕;哈拉尔阿德;魏志祥;黄维扬;颜河;于涵

机构地区：[1]Department of Applied Biology and Chemical Technology and Research Institute for Smart Energy,The Hong Kong Polytechnic University,Hong Kong 999077,China [2]Department of Chemistry and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction,Hong Kong University of Science and Technology,Hong Kong 999077,China [3]CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology,Beijing 100190,China [4]Department of Physics and Organic and Carbon Electronics Laboratories(ORaCEL),North Carolina State University,Raleigh,NC 27695,USA

出　　处：《Science China Materials》2025年第3期860-867,共8页中国科学(材料科学)(英文版)

基　　金：the Hong Kong Research Grants Council(GRF project,16303024,16310824);the support from the National Key Research and Development Program of China(2019YFA0705900)funded by Ministry of Science and Technology of China;Basic and Applied Research Major Program of Guangdong Province(2019B030302007);National Natural Science Foundation of China(NSFC,22075057);Shen Zhen Technology and Innovation Commission through Shenzhen Fundamental Research Program(JCYJ20200109140801751);Hong Kong Research Grants Council(research fellow scheme RFS2021-6S05,RIF project R6021-18,CRF project C6023-19G,GRF project 16310019,16310020,16309221,16309822);Hong Kong Innovation and Technology Commission(ITCCNERC14SC01);Foshan-HKUST(FSUST19-CAT0202);Zhongshan Municipal Bureau of Science and Technology(ZSST20SC02);Guangdong-Hong Kong-Macao Joint Laboratory(2023B1212120003);Tencent Xplorer Prize;the financial support from the RGC Senior Research Fellowship Scheme(SRFS2021-5S01).

摘　　要：Side chain engineering of small-molecule acceptors(SMAs)is a promising strategy for improving device efficiency in organic solar cells(OSCs).This study investigates the parent SMAs of BT-BO and BT-TBO,along with the newly synthesized asymmetric SMA,BT-ASY,which features branched alkyl chains and thiophene side chains substituted at theβpositions of the thiophene units,respectively.Despite exhibiting comparable optical and electrochemical properties,the PM6:BT-ASY-based device achieves a power conversion efficiency(PCE)of 18.08%representing a significant improvement over its symmetric counterparts.This enhancement is primarily attributed to improved charge mobility,extended carrier lifetimes,optimized molecular packing,and effective phase separation,as confirmed by grazing incidence wide-angle X-ray scattering measurements.Our findings highlight that asymmetric side-chain strategy enhancesπ-πstacking and electronic coupling,offering a simple yet effective approach to improving photovoltaic performance.This work underscores the potential of asymmetric structural modifications in SMAs for advancing OSC technology and renewable energy solutions.小分子受体(SMAs)的侧链工程是一种显著提升有机太阳能电池(OSCs)器件效率策略.本工作研究了BT-BO和BT-TBO的母体SMAs,以及新合成的不对称SMA BT-ASY,该分子一侧具有带支化烷基链而另一侧具有在噻吩单元β位点取代的噻吩侧链.尽管它们的光学和电化学性质相似,但基于PM6:BT-ASY的器件实现了18.08%的光电转换效率(PCE),显著优于其对称结构的光伏体系.这一提升主要归因于改善的电荷迁移率、延长的载流子寿命、优化的分子堆积和有效的相分离形貌,这些都得到了广角X射线散衍射测量的证实.我们的研究结果强调,不对称侧链策略增强了π-π堆积和电子耦合,提供了一种简单而有效的方法来提高光伏性能.这项工作突显了不对称结构修饰在小分子受体中推动有机太阳能电池技术和可再生能源解决方案的潜力.

关 键 词：organic solar cells side chain engineering active layer asymmetric acceptors thiophene side chains 

分 类 号：O62[理学—有机化学]