Degassing and Doping Unlock the Longevity Code of OECTs

• • Solvent degassing via freeze-evacuation-thawing cycles or inert gas injection reduces dissolved oxygen, increasing film crystallinity and minimizing carbonyl defects, which preserves charge transport channels and extends device lifetime under repeated electrochemical cycling. • • Ultraviolet photoelectron spectroscopy shows a work function shift from 4.0 eV in degassed chloroform to 4.3 eV in ambient chloroform for p(g3T2), quantifying oxygen's uncontrolled p-doping effect and its perturbation of electronic structure. • • Fluorinated fullerene (C60F48) serves as a stable p-dopant, counteracting oxygen-induced doping and mitigating oxidative chain scission, dopant loss, and charge trapping, thereby enhancing operational stability without compromising ionic-electronic coupling. • • The combined degassing and doping strategy achieves improved stability without the trade-offs of conventional approaches—such as hindered ion transport, increased response time, or reduced sensitivity—and remains compatible with scalable manufacturing, addressing a critical bottleneck for chronic medical monitoring and neuromorphic hardware.