Preparation and properties of gamma-PVDF/lead zirconium titanate composites

In this work, γ′-PVDF/PZT composite films with high content of γ-phase were prepared by hot-press blending, non-isothermal crystallization, coating [BMIM]BF4 on the surface of the films and annealing at high temperature in sequence. Additionally, studies were conducted on the effect of incorporating PZT on the α-to-γ′ phase transformation, as well as the dielectric and ferroelectric properties of γ′-PVDF. It is found that PZT increases the lamellar thickness of α-PVDF and promotes diffusion of [BMIM]BF4, thereby accelerating the [BMIM]BF4-assisted α-to-γ′ phase transition. Compared to neat γ′-PVDF, the dielectric constant of γ′-PVDF/PZT composites shows a marked increase while maintaining a low level of dielectric loss. Moreover, PZT addition also increases the maximum polarization intensity of γ′-PVDF. This study has presented a new approach for the efficient production of γ′-PVDF composite films that exhibit exceptional ferroelectric and dielectric properties.