Ultrathin ceramic nanowires for high interface interaction and energy density in PVDF nanocomposites

Abstract

AbstractDielectric nanocomposites with ceramic fillers have a crucial role in energy storage applications. Therefore, poly(vinylidene fluoride) (PVDF) based nanocomposites filled with 20 nm diameter, surface hydroxylated BaTiO3 nanowires (BTnws) were produced by solution‐casting method in this work, in which BTnws were synthesized via solvothermal method. The dielectric constant of BTnws/PVDF nanocomposites was 24 when the content of fillers was 10vol% at 100 Hz and the breakdown strength could increase up to 417 kV/mm before decreasing. The nanocomposites showed enhanced energy density performance and the maximum energy density could reach to 8.1J/cm3 at 320 kV/mm with 10vol% BTnws, nearly tripled that of pure PVDF at 300 kV/mm. Finite element and molecular dynamic simulation results revealed that thin BTnws could create dielectric homogeneity in the nanocomposites and have strong interface interaction with PVDF molecular. The ultrathin BTnws provided the possibility that single PVDF molecular could wrap on its surface, but this molecular wrapping pattern would not occur when the diameter of BTnws was large. Besides, the wrapping pattern could be reinforced by interactions between surface hydroxyl groups of BTnws and F atoms of PVDF molecular. Such contributions could induce good interface compatibility and lead to the improvement of energy density.