Isoindigo fluorination to enhance photovoltaic performance of donor–acceptor conjugated copolymers†
Abstract
Conjugated copolymers based on isoindigo/fluorinated isoindigo and bis(dialkylthienyl)benzodithiophene, PBDTT–ID and PBDTT–FID, were designed and synthesized for organic photovoltaic applications. The isoindigo fluorination made PBDTT–FID show high PCE of 5.52% and 7.04% in its conventional and inverted PSCs, respectively.