Organic Mixed Ionic-Electronic Conductors via Hydrolysis-Driven Alkyl-Chain Removal for High-Performance Organic Electrochemical Transistors.

Abstract

In this paper, we present a different approach to OMIECs for high-performance OECTs through the removal of alkyl chains of conjugated polymers via hydrolysis. Two conjugated polymers, referred to as P(EHE)-T and TVT(HDE)-E, were investigated. Both polymers bear thiophene units in the backbones along with branching alkyl side chains that are linked to the respective backbones through the ester linkages. Such structural features not only enable P(EHE)-T and TVT(HDE)-E to be solution processable and photo-patternable, but also allow them to remove the hydrophobic alkyl groups via hydrolysis, yielding the respective hydrophilic conjugated polymers P(OH)-T and TVT(OH)-E with hydroxymethyl groups as the side chains. The results show that thin films of P(OH)-T and TVT(OH)-E can function as OMIECs to fabricate high-performance OECTs with a notable figure of merit (µC*) value of 725.6 F cm^- ¹ V^- ¹ s^- ¹. In particular, an 8 × 8 array of OECTs with the patterned thin films of P(OH)-T was easily constructed, exhibiting sensitive and fast responsiveness toward temperature and pressure.