Effective design of A-D-A small molecules for high performance organic solar cells via F atom substitution and thiophene bridge  

作　　者：Anwang He Yuancheng Qin Weili Dai Dan Zhou Jianping Zou 

机构地区：[1]Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University

出　　处：《Chinese Chemical Letters》2019年第12期2263-2265,共3页中国化学快报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos.51663018,51703091);Outstanding Youth Funds of Jiangxi Province (No.20171BCB23056)

摘　　要：Three novel small molecules with acceptor-donor-acceptor(A-D-A) configuration,SBDT1,SBDT2 and SBDT3,where 4,8-bis(octyloxy)benzo[1,2-b:4,5-b’]dithiophene(BDT) as the electron-donating core connecting to thiophene-substituted benzothiadiazole(BT) as electron-withdrawing are reported.The effects of fluorine atoms on the photophysical properties by introducing different fluorine atoms into the benzothiadiazole unit were investigated.These SBDTs exhibit good thermal stability,excellent panchromatic absorption in solution and film.SBDT2 and SBDT3 with fluorine-substituted BT possess a relatively deeper the highest occupied molecular orbital(HOMO).These A-D-A type molecules were treated as donor and PC71 BM as acceptor in bulk heterojunction(BHJ) small-molecule organic solar cells(SMOSCs).Among them,device based on SBDT2 gave the best device performance with a PCE of 5.06%with Jsc of 10.56 mA/cm^2,Voc of 0.85 V,fill factor(FF) of 56.4%.These studies indicate that proper incorporation of fluorine atoms is an effective way to increase the efficiency of organic solar cells.Three novel small molecules with acceptor-donor-acceptor（A-D-A） configuration,SBDT1,SBDT2 and SBDT3,where 4,8-bis（octyloxy）benzo[1,2-b:4,5-b’]dithiophene（BDT） as the electron-donating core connecting to thiophene-substituted benzothiadiazole（BT） as electron-withdrawing are reported.The effects of fluorine atoms on the photophysical properties by introducing different fluorine atoms into the benzothiadiazole unit were investigated.These SBDTs exhibit good thermal stability,excellent panchromatic absorption in solution and film.SBDT2 and SBDT3 with fluorine-substituted BT possess a relatively deeper the highest occupied molecular orbital（HOMO）.These A-D-A type molecules were treated as donor and PC71 BM as acceptor in bulk heterojunction（BHJ） small-molecule organic solar cells（SMOSCs）.Among them,device based on SBDT2 gave the best device performance with a PCE of 5.06%with Jsc of 10.56 mA/cm2,Voc of 0.85 V,fill factor（FF） of 56.4%.These studies indicate that proper incorporation of fluorine atoms is an effective way to increase the efficiency of organic solar cells.

关 键 词：A-D-A small molecule BENZOTHIADIAZOLE FLUORINATION Organic solar cells 

分 类 号：TQ317[化学工程—高聚物工业] TM914.4[电气工程—电力电子与电力传动]