Proton Irradiation Effects on the Pyroelectric Properties of P-Type Bismuth Antimonide/Poly(vinylidene fluoride-trifluoroethylene) Composite Films

Organic pyroelectric materials are widely applied as temperature sensors in wearable electronic devices due to their good biocompatibility and stability. Real-time monitoring of the physiological state of the human body requires pyroelectric materials with a fast response time and large output voltage. In this study, the pyroelectric characteristics of poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) films are improved with the use of commercial inorganic P-type bismuth antimonide (P-Bi2Te3) fillers. Composite films with 0.2 wt% P-Bi2Te3 increase the pyroelectric response time and voltage by improving the thermal diffusivity and enhancing the beta-phase content, respectively. Proton irradiation results in further improvement of the pyroelectric response time from 22 to 0.5 s. The proton irradiation-induced ionization energy loss improves the conductivity of the composite films, thereby enhancing the pyroelectric response time. These results show that P-Bi2Te3 doping is beneficial for improving the pyroelectric properties of P(VDF-TrFE) and that proton irradiation is an effective method for further improving the response time of inorganic-organic composite films.