Carbazolebis(thiadiazole)-core based non-fused ring electron acceptors for efficient organic solar cells  

作　　者：Yongjie Cui Peipei Zhu Xinxin Xia Xinhui Lu Xunfan Liao Yiwang Chen 

机构地区：[1]State Key Laboratory for Modification of Chemical Fibers and Polymer Materials and College of Materials Science and Engineering,Donghua University,Shanghai 201620,China [2]National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education,College of Chemistry and Chemical Engineering,Jiangxi Normal University,Nanchang 330022,China [3]Department of Physics,Chinese University of Hong Kong,New Territories,Hong Kong 999077,China

出　　处：《Chinese Chemical Letters》2023年第8期322-327,共6页中国化学快报（英文版）

基　　金：This work was financially supported by the National Natural Science Foundation of China(NSFC,Nos.51973032,21905043 and 51833004);the“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.19CG36);the Jiangxi Provincial Natural Science Foundation(Nos.20212ACB203005 and 20212BAB213018);the Thousand Talents Plan of Jiangxi Province(No.jxsq2019101051);the Jiangxi Provincial Education Department Science and Technology Research Foundation(No.GJJ210310);X.Xia and X.Lu acknowledge the financial support from Research Grants Council(RGC)of Hong Kong(General Research Fund No.14303519);Y.Chen expresses thanks for the support from the Fundamental Research Funds for the Central Universities and Graduate Student Innovation Fund of Donghua University(No.CUSF-DH-D-2021008).

摘　　要：Non-fused ring electron acceptors(NFREAs)have a broad application prospect in the commercialization of organic solar cells(OSCs)due to the advantages of simple synthesis and low cost.The selection of intermediate block cores of non-fused frameworks and the establishment of the relationship between molecular structure and device performance are crucial for the realization of high-performance OSCs.Herein,two A-D-A’-D-A type NFREAs namely CBTBO-4F and CBTBO-4Cl,constructed with a novel electron-deficient block unit N-(2-butyloctyl)-carbazole[3,4-c:5,6-c]bis[1,2,5]thiadiazole(CBT)and bridging unit 4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b’]dithiophene(DTC)coupling with different terminals(IC-2F/2Cl),were designed and synthesized.The two NFREAs feature broad and strong photoresponse from 500 nm to 900 nm due to the strong intramolecular charge transfer characteristics.Compared with CBTBO-4F,CBTBO-4Cl shows better molecular planarity,stronger crystallinity,more ordered molecular stacking,larger van der Waals surface,lower energy level and better active layer morphology,contributing to much better charge separation and transport behaviors in its based devices.As a result,the CBTBO-4Cl based device obtains a higher power conversion efficiency of 10.18%with an open-circuit voltage of 0.80 V and a short-circuit current density of 21.20 mA/cm^(2).These results not only demonstrate the great potential of CBT,a new building block of the benzothiazole family,in the construction of high-performance organic conjugated semiconductors,but also suggest that the terminal chlorination is an effective strategy to improve device performance.

关 键 词：Carbazolebis(thiadiazole) Non-fused ring electron acceptors A-D-A’-D-A type Molecular planarity Organic solar cells 

分 类 号：TM914.4[电气工程—电力电子与电力传动]