Ferro- and piezo-electric properties of a poly(vinyl fluoride) film with high ferro- to para-electric phase transition temperature

Abstract

Excellent ferro- and piezo-electric performance is proposed for the first time in poly(vinyl fluoride) (PVF) in the beta crystal phase of a hexagonal plane and high crystallinity. A Currie phase transition from ferro- to para-electric is found at 168 °C, which is the highest among the reported polymeric ferroelectrics. At room temperature, a coercive electric field as high as 120 MV m⁻¹ and a remnant displacement of 5 μC cm⁻² are obtained on D–E loops. After polarized at 300 MV m⁻¹, a relatively large piezoelectric coefficient of −11 pC N⁻¹ is detected. Regarding its high depolarization temperature and facile film processing procedure, PVF ferroelectric films may attract interest and find particular applications at elevated temperatures.