Fully Stretchable Ionically Tunable Organic Electrochemical Transistors for Wearable Adaptive Logic Bioelectronics

Ionically tunable soft electronic systems that integrate mechanical stretchability, functional adaptability, and intuitive state readout are critical for next-generation bioelectronics. Rather than introducing a new material, we demonstrate that a dual-doped PEDOT/PSS composite operates as an adaptive electrochemical medium in which ionic states encode logic, memory, and optical visibility within a single stretchable architecture. The dual-doping strategy simultaneously enhances electrical stability and mechanical robustness under repeated deformation, while ionic modulation of the channel induces a reversible electrochromic transition that directly visualizes the device's operational and memory states. Through electrolyte modulation, a single organic electrochemical transistor (OECT) can be ionically tuned to function as logic transistors for inverters, NAND, and NOR gates, or as a synaptic transistor exhibiting long-term memory, with its state concurrently displayed through color modulation. Leveraging this coupled electrical-optical functionality, we demonstrate mechano-electrochromic synaptic skins and a wearable adaptive logic bioelectronic system, establishing an ionically tunable and visually interpretable platform for interactive soft bioelectronics.