Fast and Durable Nanofiber Mat Channel Organic Electrochemical Transistors.

Bioelectronic devices that offer real-time measurements, biological signal processing, and continuous monitoring while maintaining stable performance are in high demand. The materials used in organic electrochemical transistors (OECTs) demonstrate high transconductance (GM) and excellent biocompatibility, making them suitable for bioelectronics in a biological environment. However, ion migration in OECTs induces a delayed response time and low cut-off frequency, and the adverse biological environment causes OECT durability problems. Herein, we present OECTs with a faster response time and improved durability, made possible by using a nanofiber mat channel of a conventional OECT structure. Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)/polyacrylamide (PAAm) nanofiber mat channel OECTs are fabricated and subjected to various durability tests for the first time based on continuous measurements and mechanical stability assessments. The results indicate that the nanofiber mat channel OECTs have a faster response time and longer life spans compared to those of film channel OECTs. The improvements can be attributed to the increased surface area and fibrous structure of the nanofiber mat channel. Furthermore, the hydrogel helps to maintain the structure of the nanofiber, facilitates material exchange, and eliminates the need for a crosslinker.