Utilizing Linear Polymers to Optimize Remanent Polarization and Construct Multilayer Interfaces to Obtain High-Efficient Poly(vinylidene fluoride)-Based Energy-Storage Composites

Abstract

Polyvinylidene fluoride (PVDF) has been widely studied as a ferroelectric polymer for energy dielectric applications. However, high-polarization PVDF has a low-efficiency issue, owing to high residual polarization. This study introduces highly insulating, low-loss linear polycarbonate (PC) into PVDF-based dielectrics. The PC layer optimizes the remanent polarization (D r ) of PVDF and maintains it within a small range, thus achieving a high charge−discharge efficiency. The multilayer structural design of PVDF-based dielectrics adjusts the interlayer electric field distribution. We have thoroughly studied the influence of the number and proportion of PC layers on the polarization and breakdown of the multilayer films as well as achieved collaborative regulation of dual parameters. Our results indicate that three layers of PC-PVDF-PC (CPC) films containing a large proportion of PC can polarize under high electric fields and maintain excellent charge−discharge efficiency, achieving an energy density and efficiency of 11.48 J/cm 3 and 92.4%, respectively, under 610 kV/mm. The PVDF-based dielectrics prepared in this work are all organic films, and their flexibility and foldability are conducive to the preparation of flexible devices.

Influence of Nano-CeO2 and Graphene Nanoplatelets on the Conductivity and Dielectric Properties of Poly(vinylidene fluoride) Nanocomposite Films

“…Thus, to obtain excellent nanocomposite (NC) material, it is important to form an excellent linkage between the host matrix and the nanofiller. Poly­(vinylidene fluoride) (PVDF) is a thermoplastic that displays good flexibility, excellent piezo, pyro, and ferroelectric properties, high thermal stability, high chemical stability, high resistance to UV irradiation, high mechanical strength, and high dielectric constant. − The piezo and pyroelectric properties of PVDF depend on its different crystalline phases and the C–F dipoles which orient along the polymeric chains . The well-known and most frequently observed crystalline phases of PVDF are α, β, γ, and δ with distinct macromolecular chain confirmations .…”