High-hole-mobility PEDOT:PSS fiber-OECTs for future bio-hybrid technologies

Conductive fibers are transforming wearable electronics, offering potential for customized electronic textiles and applications in wearable bioelectronics. Organic Electrochemical Transistors (OECTs) stand out as devices for sensing various stimuli from the human body. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), a widely studied polymer, offers a promising pathway for fabricating these conductive fibers. We demonstrate that the synergistic effects from fiber alignment and contact engineering produce PEDOT:PSS fiber-OECTs with high hole mobilities exceeding 45 cm2/Vs. Using these fiber-OECTs, we develop fiber-electrochemical neuromorphic organic devices (fiber-ENODes), exhibiting synaptic weight updates in response to dopamine. With a form factor akin to neuronal axon terminals, these fibers hold great promise for neuromorphic and bio-hybrid technologies. Investigating charge transport mechanisms and charge trapping in PEDOT:PSS fiber-OECTs will unveil the fundamental mechanisms and design rules crucial for organic materials working at the at the bio-hybrid interface.