2,1,3-Benzooxadiazole, thiophene and benzodithiophene based random copolymers for organic photovoltaics: thiophene versus thieno[3,2-b]thiophene as pi-conjugated linkers


Goker S. , HIZALAN G., AKTAS E., KUTKAN S., ÇIRPAN A. , TOPPARE L.

NEW JOURNAL OF CHEMISTRY, vol.40, no.12, pp.10455-10464, 2016 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 40 Issue: 12
  • Publication Date: 2016
  • Doi Number: 10.1039/c6nj02469f
  • Title of Journal : NEW JOURNAL OF CHEMISTRY
  • Page Numbers: pp.10455-10464

Abstract

Three conjugated random copolymers comprising benzodithiophene and thiophene as the donor units and benzooxadiazole as the acceptor unit, spaced with thiophene and thieno[3,2-b]thiophene pi-bridges, were designed and synthesized. The effects of different linkers on the optical and electrochemical properties were investigated. The polymer containing a thieno[3,2-b]thiophene pi-bridge revealed a red shifted absorption compared to its thiophene analogue. Morphological and photovoltaic properties of a polymer:fullerene blend film were investigated. The blend of one of the random copolymers (P-2) and PC71BM ([6,6]-phenyl-C-71-butyric acid methyl ester) revealed a photovoltaic performance efficiency of 5.17% due to the high short-circuit current density and fill factor.