Tuning Polarity in Naphthalenediimide-Based Field-Effect Transistors through Incorporation of Alkoxy-Bithiophene Unit

Abstract

The recent development of low-band-gap polymers comprising alternating donor and acceptor units in the backbone led to an improvement in the charge transport properties of organic field-effect transistors (OFETs). Among many conjugated semiconducting materials, P(NDI2OD-T2) (also known as Polyera ActivInk N2200) is well-known as a top-performing n-channel material comprising a naphthalenediimide acceptor and a bithiophene donor units. Herein, we report ambipolar OFETs based on (NDI2OD-T2) analogous polymers by introducing simultaneously the alkoxy-bithiophene unit and changing of alkyl branching point. This study advances our fundamental understanding of how polymer structure influences dominant polarity of charge carriers and reveals a new synthetic strategy for the design of ambipolar semiconducting materials.