Amphiphilic Interface-Mediated Ion Doping for High Performance Organic Electrochemical Transistors with Hydrophobic Polymers

An organic electrochemical transistor (OECT) is one of the promising devices for bioelectronics due to its high transconductance, encompassing low operation voltage, and good compatibility with aqueous conditions. Despite these advantages, the challenge of balancing ion penetration and electron transport remains a significant issue in OECTs. Herein, we present an amphiphilic interface modification strategy to successfully prepare OECTs in aqueous conditions based on a high-mobility hydrophobic polypyrrole derivative. An amphiphilic interface mixed with an amphiphilic polymer and the active layer markedly promotes ion penetration and results in a significant improvement in performance, with the switch time reduced from several seconds to nearly 100 ms and the transconductance increased by an order of magnitude. The high-performance OECTs fabricated by this method show promising applications in high-performance neuromorphic devices and ECG recording in advancing the field of electrochemical transistors.