Crystallinity Engineering Induced High-Sensitive Thermal Response in Polyvinylidene Fluoride by x-Ray Irradiation

Polyvinylidene fluoride (PVDF) and its copolymers have garnered significant interest for flexible and wearable sensors. However, the sensitivity of PVDF-based sensors is limited by their relatively low pyroelectric properties compared to those of inorganic ferroelectric materials. In this study, we report on poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) films exposed to x-ray irradiation to increase the crystallinity and β-phase content. This increase in crystallinity and β-phase content ultimately improved the pyroelectric coefficient (150.9 μC m −2 K −1 ) by almost more than five times. The sensors, based on the irradiated P(VDF-TrFE) films, showed an outstanding thermal voltage sensitivity of 15.07 V K −1 and a current sensitivity of 12.19 nA K −1 . The sensors exhibited excellent linear temperature sensing and a precision infrared detector, making them promising candidates for self-powered electronic skin in human-machine interaction applications.