Cyanated isoindigos for n-type and ambipolar organic thin film transistors†
Abstract
A set of three core-cyanated isoindigos was synthesized by palladium-catalyzed cyanation of core-brominated isoindigos. With decreased LUMO level to −3.88 eV, the dicyanated isoindigo 5 showed ambient-stable electron mobility up to 0.044 cm2 V−1 s−1 in OTFTs with SAMs of TPA, while it exhibited ambipolar charge transport behaviour (0.11 cm2 V−1 s−1 for electrons and 0.045 cm2 V−1 s−1 for holes) on FOPA-modified substrates.