Single‐Junction Binary‐Blend Nonfullerene Polymer Solar Cells with 12.1% Efficiency. Issue 18 (10th March 2017)

• Record Type: Journal Article
• Authors: Zhao, Fuwen; Dai, Shuixing; Wu, Yang; Zhang, Qianqian; Wang, Jiayu; Jiang, Li; Ling, Qidan; Wei, Zhixiang; Ma, Wei; You, Wei; Wang, Chunru; Zhan, Xiaowei
• Is Part Of: Advanced materials. Volume 29:Issue 18(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-03-10
• Subjects: fluorination -- fused‐ring electron acceptors -- nonfullerene -- polymer solar cells; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201700144
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract : A new fluorinated nonfullerene acceptor, ITIC‐Th1, has been designed and synthesized by introducing fluorine (F) atoms onto the end‐capping group 1, 1‐dicyanomethylene‐3‐indanone (IC). On the one hand, incorporation of F would improve intramolecular interaction, enhance the push–pull effect between the donor unit indacenodithieno[3, 2‐b]thiophene and the acceptor unit IC due to electron‐withdrawing effect of F, and finally adjust energy levels and reduce bandgap, which is beneficial to light harvesting and enhancing short‐circuit current density ( J SC ). On the other hand, incorporation of F would improve intermolecular interactions through CF···S, CF···H, and CF···π noncovalent interactions and enhance electron mobility, which is beneficial to enhancing J SC and fill factor. Indeed, the results show that fluorinated ITIC‐Th1 exhibits redshifted absorption, smaller optical bandgap, and higher electron mobility than the nonfluorinated ITIC‐Th. Furthermore, nonfullerene organic solar cells (OSCs) based on fluorinated ITIC‐Th1 electron acceptor and a wide‐bandgap polymer donor FTAZ based on benzodithiophene and benzotriazole exhibit power conversion efficiency (PCE) as high as 12.1%, significantly higher than that of nonfluorinated ITIC‐Th (8.88%). The PCE of 12.1% is the highest in fullerene and nonfullerene‐based single‐junction binary‐blend OSCs. Moreover, the OSCs based on FTAZ:ITIC‐Th1 show much better efficiency and better stability than the control devices based on FTAZ:PC71 BM (PCE = 5.22%). Abstract : Single‐junction binary‐blend nonfullerene polymer solar cells based on fluorinated acceptor ITIC‐Th1 afford power conversion efficiency of 12.1%, which is much higher than those of nonfluorinated ITIC‐Th (8.88%) and PC71 BM (5.22%) counterparts under the same condition. Moreover, the nonfullerene devices exhibit better thermal stability than the fullerene devices.