Enhancement the photovoltaic performance of conjugated polymer based on simple head-to-head alkylthio side chains engineered bithiophene  

作　　者：Zuoji Liu Chengjia Bao Guangjun Zhang Kai Zhang Gangtie Lei Qiang Zhang Qiang Peng Yu Liu 

机构地区：[1]School of Materials Science and Engineering,Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications,Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering,National Experimental Demonstration Center for Materials Science and Engineering,Changzhou University,Changzhou 213164,China [2]College of Chemistry,Key Lab of Environment-Friendly Chemistry and Application in the Ministry of Education,Xiangtan University,Xiangtan 411105,China [3]Key Laboratory of Green Chemistry and Technology of Ministry of Education,College of Chemistry,and State Key Laboratory of Polymer Materials Engineering,Sichuan University,Chengdu 610065,China

出　　处：《Chinese Chemical Letters》2020年第9期2459-2464,共6页中国化学快报（英文版）

基　　金：financially supported by grants from the National Natural Science Foundation of China(Nos.51573154,51673031);The Natural Science Foundation of Jiangsu Higher Institutions of China(No.18KJA480001);the Youth Science and Technology Foundation of Sichuan Province(No.2013JQ0032);the key Laboratory of Environment-Friendly Chemistry and Applications of Ministry of Education(No.2018HJYH01);the Natural Science Foundation of Jiangsu Province(No.BK20141151)。

摘　　要：In this article,three novel and simple molecular structure with donor-acceptor(D-A) type copolymers via only head-to-head alkoxy(OR) and/or alkylthio(SR) side chains onto the bithiophene(BT) as donor units and fluorinated benzotriazole(FBTA) as acceptor unit,namely,PBTOR-FBTA,PBTOSR-FBTA and PBTSRFBTA,were successfully designed and synthesized.The impacts of sulfur-oxygen(S…O) or sulfur-sulfur(S-S) noncovalent interactions on their physicochemical properties,molecular stacking,carrier mobility,morphologies of blend films,as well as their photovoltaic performance were deeply and systematically studied.The introduction of SR side-chains suddenly lowered the highest occupied molecular orbital(HOMO) energy levels,blue-shifted absorption,enhanced π-π stacking,as well as improved morphology of the photoactive layer blends in comparison with the re ference polymer without SR side-chain.Polymer solar cells(PSCs) were fabricated to estimate their photovoltaic performance of the polymers.Under an optimized blend ratio of PBTSR-FBTA:PC71BM(1:0.8,w/w),the PBTSR-FBTAbased device exhibits a higher power conversion efficiency(PCE) of 6.25%,which is about 3.34 and 1.87 folds than that of the PBTOR-FBTA and PBTOSR-FBTA-based devices,respectively.Our research results demonstrate that the modification of the simple and low-cost SR side chains is an effective strategy to improve the photovoltaic performance of the polymers.

关 键 词：BITHIOPHENE Fuorobenzotriazole Alkoxy side chain Alkylthio side chain Polymer solar cells 

分 类 号：TQ317[化学工程—高聚物工业]