Thienopyrroledione and benzodithiophene/thiophene-based random terpolymer for polymer solar cells with improved fill factor. (May 2017)

• Record Type: Journal Article
• Authors: Bang, Su-Mi; Park, Jung-hyun; Kang, Sungkyoung; Lee, You-Sun; Lim, Bogyu; Heo, Hyojung; Lee, Jaechol; Lee, Youngu; Na, Seok-In
• Is Part Of: Dyes and pigments. Volume 140(2017)
• Page Start: 229
• Page End: 235
• Publication Date: 2017-05
• Subjects: Polymer solar cell -- Improved fill factor -- Terthiophene -- Random polymer; Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2017.01.049
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: A new random conjugated terpolymer, coded as LGC-D054, was designed and synthesized. It is composed of N -alkylthieno[3, 4- c ]pyrrole-4, 6-dione (TPD) as an electron-accepting unit, and benzodithiophene (BDT) and terthiophene as electron-donating units into the polymer backbone. The optical, electrochemical, and photovoltaic properties of the terpolymer were investigated. The polymer displayed an optical bandgap of 1.81 eV, with a highest occupied molecular orbital (HOMO) level of −5.25 eV. The bulk-heterojunction (BHJ) polymer solar cell (PSC) with the blend film based on LGC-D054:PC71 BM exhibited a power conversion efficiency (PCE) of 4.46% with the short circuit current density (Jsc ) of 8.71 mA/cm 2 and a relatively high fill factor (FF) of 61.21%. After introducing 1, 8-diiodooctane (DIO), BHJ film showed better phase separation and larger domain size. Furthermore, this optimized morphology promotes improved hole and electron mobilities, leading to a promising PCE of 5.08% with improved Jsc of 9.08 mA/cm 2 and high FF of 66.02%. Graphical abstract: Highlights: A new random terpolymer, based on TPD, BDT, and terthiophene as the donor, has been synthesized. The thermal, optical, and electrochemical properties of the LGC-D054 were characterized. The PSC based on LGC-D054:PC71 BM blend film demonstrated PCE of 4.46%. The PSC using LGC-D054 showed an improved FF, higher than conventional TPD-BDT based polymers. After DIO treatment, PCE was further improved from 4.46 to 5.08%.