Fluorene-fused ladder-type non-fullerene small molecule acceptors for high-performance polymer solar cells. (13th March 2019)

• Record Type: Journal Article
• Authors: Ming, Ruijie; Zhang, Miao; Gao, Wei; Ning, Weimin; Luo, Zhenghui; Zhong, Cheng; Zhang, Fujun; Yang, Chuluo
• Is Part Of: Materials chemistry frontiers. Volume 3:Number 4(2019)
• Page Start: 709
• Page End: 715
• Publication Date: 2019-03-13
• Subjects: Materials science -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1039/c9qm00013e
• Languages: English
• ISSNs: 2052-1529

Abstract

Abstract : FTTCN-based PSCs exhibited a PCE of 10.56%, with the highest FF of 73.82% for fluorene-based SMAs. Abstract : In this work, we designed and synthesized two new small molecule acceptors (SMAs), namely FTTCN and FTTCN-M, structured with a coplanar central core based on a fluorene-fused ladder-type donor and electron-withdrawing end-capping groups (CPTCN and CPTCN-M). Compared to FTTCN-M, FTTCN exhibits slightly redshifted absorption, higher electron mobility and a more favorable morphology of the blend film. FTTCN-based polymer solar cells (PSCs) paired with p-type polymer PBDB-T achieved a power conversion efficiency (PCE) of 10.56%, with an open-circuit voltage ( V OC ) of 0.90 V, a short-circuit current density ( J SC ) of 15.89 mA cm −2 and a fill factor (FF) of 73.82%, which is slightly higher than that of FTTCN-M-based devices (a PCE of 10.08% alone with a V OC of 0.93 V, a J SC of 15.19 mA cm −2 and a FF of 71.37%). To the best of our knowledge, the FF of 73.82% is the highest value for fluorene-based PSCs reported to date. The higher J SC and FF of the FTTCN-based device could be attributed to the lower charge recombination, more balanced carrier mobility, and more favorable surface morphology of the PBDB-T:FTTCN blend film than those of the PBDB-T:FTTCN-M blend film. This work revealed that a fluorene-fused ladder-type donor exhibits great potential in constructing high-performance non-fullerene SMAs and optimizing end-capping groups.