Side‐chain induced chirality in diketopyrrolopyrrole based polymers

Abstract

AbstractChiral all‐π‐conjugated conducting polymers are of significant importance because of their promising aspects ranging from organic electronics, organic spin filters, efficient water splitting materials, magneto‐optic materials to circularly polarized light emitters. Here, we report the synthesis and characterization of the first series of diketopyrrolopyrrole based chiral low band‐gap alternating copolymers. Alongside characterizations by UV and CD spectroscopy, AFM and FESEM were further performed to understand the morphology of the optically active polymers. The stereochemistry of the side‐chains on TDPP unit played a pivotal role in determining chiroptical properties and supramolecular self‐assembly of the copolymers in solution which lead to layer‐by‐layer helical morphology in solid‐state. Interestingly, D‐A intramolecular charge transfer transition showed Cotton effect with bimodal nature, which is remarkably stronger than the π‐π* transition.