High open-circuit voltage solution-processed organic solar cells based on a star-shaped small molecule end-capped with a new rhodanine derivative  

作　　者：Yuanhang Zhou Weichao Chen Zhengkun Du Dangqiang Zhu Dan Ouyang Liangliang Han Renqiang Yang 

机构地区：[1]CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences [2]University of Chinese Academy of Sciences

出　　处：《Science China Chemistry》2015年第2期357-363,共7页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(51173199,51211140346,61405209);the National Basic Research Program of China(2014CB643501,2010DFA52310);the Shandong Provincial Natural Science Foundation(ZR2011BZ007);the Qingdao Municipal Science and Technology Program(11-2-4-22-hz)

摘　　要：A new star-shaped small molecule named TCNR3TTPA,with a triphenylamine(TPA)unit as the central building block and2-(1,1-dicyanomethylene)-3-octyl rhodanine(CNR)as the end-capped group,has been designed and synthesized.TCNR3TTPA showed a deep highest occupied molecular orbital(HOMO)energy level( 5.60 e V)and broad absorption.The solution-processed bulk heterojunction(BHJ)solar cells based on TCNR3TTPA:PC61BM(1:1,w/w)exhibited a high open-circuit voltage(Voc)of 0.99 V,a short-circuit current density(Jsc)of 5.76 m A/cm2,and a power conversion efficiency(PCE)of 2.50%under the illumination of AM 1.5 G,100 m W/cm2.The high Voc is ascribed to the strong electron-with-drawing ability of the end-capped 2-(1,1-dicyanomethylene)-3-octyl rhodanine group.These results demonstrated that the Voc of small-molecule organic solar cells could be increased by introducing a strong electron-withdrawing end-capped block,and that this is an effective strategy to design high-performance small molecules for organic solar cells.A new star-shaped small molecule named TCNR3TTPA, with a triphenylamine （TPA） unit as the central building block and 2-（1,1-dicyanomethylene）-3-octyl rhodanine （CNR） as the end-capped group, has been designed and synthesized. TCNR3TTPA showed a deep highest occupied molecular orbital （HOMO） energy level （-5.60 eV） and broad absorption. The solution-processed bulk heterojunction （BHJ） solar cells based on TCNR3TTPA：PC61BM （1：1, w/w） exhibited a high open-circuit voltage （Voc） of 0.99 V, a short-circuit current density （Jsc） of 5.76 mA/cm2, and a power conversion efficiency （PCE） of 2.50% under the illumination of AM 1.5 G, 100 mW/cm2. The high Voc is ascribed to the strong electron-with- draw- ing ability of the end-capped 2-（1,1-dicyanomethylene）-3-octyl rhodanine group. These results demonstrated that the Voc of small-molecule organic solar cells could be increased by introducing a strong electron-withdrawing end-capped block, and that this is an effective strategy to design high-performance small molecules for organic solar cells.

关 键 词：organic solar cells open-circuit voltage triphenylamine rhodanine derivative 

分 类 号：TM914.4[电气工程—电力电子与电力传动] O631.1[理学—高分子化学]