Impact of regio-isomeric monochlorinated end groups on packing mode,miscibility,and photovoltaic performance of asymmetric selenophene-fused M-series acceptors  

作　　者：Ruochuan Liao Changquan Tang Yunlong Ma Qingdong Zheng 

机构地区：[1]State Key Laboratory of Structural Chemistry,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China [2]State Key Laboratory of Coordination Chemistry,College of Engineering and Applied Sciences,Nanjing University,Nanjing 210023,China [3]University of ChineseAcademyof Sciences,Beijing 100049,China

出　　处：《Chinese Chemical Letters》2023年第12期251-256,共6页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.52130306,22075287,22101285);the Program of Youth Innovation Promotion Association CAS(No.2021299).

摘　　要：Optimal bulk-heterojunction(BHJ)morphology is crucial for efficient charge transport and good photovoltaic performance in organic solar cells(OSCs).Yet,the correlation between chemical structures of nonfullerene acceptors(NFAs)and molecular interaction in the BHJ blends remains opaque.Herein,we study three isomeric NFAs referred to as MQ1-x(x=β,y,or 8)that shared an asymmetric selenophene-fused heteroheptacene backbone end-capped by two monochlorinated end groups.Remarkably,miscibility between the polymer donor of PM6 and MQ1-x successively elevates as the chlorine atoms move fromβ-,to y-,to 8-position of terminals.Combined with the varied molecular crystallinity of these NFAs,diverse BHJ morphologies are observed in their blend films.As a result,the MQ1-8-based devices present the highest PCE of 12.08%owing to the efficient charge dissociation and transport induced by the compact molecular packing and optimal BHJ morphology.Our investigation provides a new insight in the material design that has a good balance in molecular packing and film morphology for high-performance OSCs.

关 键 词：Organic solar cells MISCIBILITY Noncovalent interaction Chlorinated isomers Molecular packing 

分 类 号：TM914.4[电气工程—电力电子与电力传动] TB34[一般工业技术—材料科学与工程]