Effect of AgNbO3 Morphology on Dielectric and Energy Storage Properties of Polyvinylidene Fluoride-Based Nanocomposites

Introducing high dielectric constant ceramics into polymerscanimprove the dielectric constant and energy storage performance ofcomposites without reducing the breakdown resistance of polymers.The remnant polarization of the antiferroelectric material is verysmall, and it has a high saturation polarization, which is beneficialto improving the energy storage density. In this study, three differentmicrostructures of AgNbO3 particles, C-AN, S-AN, and H-AN,were prepared by the co-precipitation method, traditional solid phasemethod, and hydrothermal method, respectively. Among them, C-NPS isa nanometer powder and S-AN and H-AN are micron powders. The surfaceof the particles was modified with silane coupling agent KH560 toimprove the compatibility of the inorganic-organic interface.Composite materials were prepared by the casting method. The resultsshow that the C-AN nanoparticle has a large specific surface area,small particle size, and uniform size distribution and its dispersionin the PVDF (polyvinylidene fluoride) matrix is the best. The highsaturation polarization of the antiferroelectric AgNbO3 filler under a high electric field can induce the composite to producea high P (max) (maximum polarization) valueand reduce P (r) (remanent polarization),thereby ultimately increasing the energy storage density of the nanocomposite.The energy storage density of the 0.3 wt % C-AN/PVDF composite is6.03 J/cm(3) under the electric field of 300 kV/mm.