Halogenated thiophene substitutions on quinoxaline unit to achieve morphology optimization in efficient organic solar cells  

作　　者：Dingding Qiu Jianqi Zhang Kun Lu Zhixiang Wei 

机构地区：[1]CAS Key Laboratory of Nanosystem and Hierarchical Fabrication,National Center for Nanoscience and Technology,Beijing 100190,China [2]Sino-Danish Center for Education and Research,Sino-Danish College,University of Chinese Academy of Sciences,Beijing 100049,China [3]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Nano Research》2023年第9期11630-11637,共8页纳米研究（英文版）

基　　金：We acknowledge the financial support provided by the National Natural Science Foundation of China(No.51973043);the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB36000000).

摘　　要：Halogenated thiophenes are generally used units for constructing organic semiconductor materials for photovoltaic applications.Here,we introduced thiophene,2-bromothiophene,and 2-chlorothiophene units to the central core of quinoxaline-based acceptors and obtained three acceptors,Qx-H,Qx-Br,and Qx-Cl,respectively.Compared with Qx-H,Qx-Br and Qx-Cl showed enhanced absorption,down-shifted energy levels,improved crystallinity,and reduced energy disorder.The improved crystallinity significantly optimized the blend morphology,leading to efficient charge generation and transport and,therefore,less bimolecular recombination.Eventually,PM6:Qx-Br-based devices exhibited an outstanding power conversion efficiency of 17.42%with a high open-circuit voltage(VOC)of 0.915 V.Furthermore,Y6 was introduced into the PM6:Qx-Br binary system to improve the light utilization,and the resulting ternary devices delivered a high PCE of 18.36%.This study demonstrated the great potential of halogenated thiophene substitution in quinoxaline-based acceptors for building high-performance organic solar cell acceptor materials.

关 键 词：halogenated thiophene units non-fullerene acceptors organic solar cells quinoxaline acceptors morphology optimization 

分 类 号：TM914.4[电气工程—电力电子与电力传动]