Improved interfacial polarization of poly(vinylidene fluoride‐chlorotrifluoroethylene) composite with BaTiO3@polyaniline core‐shell fiber

Abstract

AbstractWith the advantages of self‐healing and high breakdown, polymer film is the promising candidate in next‐generation dielectric capacitor. However, the energy density of polymer dielectrics needs to be further improved for the film capacitor with superior energy storage performance. It is particularly important to explore the energy loss mechanism under external electric field based on the interfacial effect in polymer composite. In this work, the energy storage capability of poly(vinylidene fluoride‐chlorotrifluoroethylene) composite with core‐shell BaTiO3@polyainline (BTO@PANI) fiber has been investigated. The electrical conductivity of BTO@PANI is regulated by controlling acid concentration in microemulsion polymerization. The dielectric constant of 0.1 wt% composite increases to 27.7 with low dielectric loss of 0.0576 at 10 kHz. The released energy density of 0.1 wt% composite reaches 10.03 J/cm3 with charge–discharge efficiency of 70.5% at 300 MV/m. The core‐shell BTO@PANI fibers are served as the trapping sites of charge carriers, which contributes to the formation of microcapacitor in composite. As an interactive channel, PANI fiber provides diffusion paths for the charge carriers, thus conducting the polarized response of composite. Polymer composite with fibrous structure demonstrates large polarization, and this work sheds light on the energy loss related to the conductivity of interface in polymer dielectric film.