Effect of electron-withdrawing units on triphenylamine-based small molecules for solution-processed organic solar cells

作     者：Yifan Wang Huitao Bai Pei Cheng Mingyu Zhang Xiaowei Zhan 

作者机构：CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Materials Science and Engineering College of Engineering Peking University 

出 版 物：《Science China Chemistry》 (中国科学（化学英文版）)

年 卷 期：2015年第58卷第2期

页      面：331-338页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 080502[工学-材料学] 070303[理学-有机化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 

基　　金：supported by the National Natural Science Foundation of China(21025418,51261130582) the National Basic Research Program of China(2011CB808401) the Chinese Academy of Sciences 

主　　题：organic solar cell small molecule triphenylamine electron-withdrawing unit 

摘      要：Organic small molecules （TPA-BT3T, TPA-PT3T, and TPA-DFBT3T） using triphenylamine as a donor unit, terthiophene as a bridge, and benzo-2,1,3-thiadiazole （BT）, [1,2,5]thiadiazolo[3,4-e]pyridine （PT） or 5,6-difluorobenzo[c][1,2,5]thiadiazole （DFBT） as an acceptor unit were designed and synthesized through Suzuki coupling reactions. These molecules exhibited good thermal stability with decomposition temperatures over 380℃ and broad absorption from 300 to 700 nm. Photovoltaic devices were fabricated with these small molecules as donors and PC71BM as an acceptor. The TPA-BT3T based devices exhibited a power conversion efficiency of 2.89%, higher than those of the TPA-PT3T- and TPA-DFBT3T-based devices （1.34% and 1.54% respectively）. The effects of electron-withdrawing units on absorption, energy level, charge transport, morphology, and photovoltaic properties also were investigated.