Coating Fluoropolymer on BaTiO3 Nanoparticles to Boost Permittivity and Energy Density of Polymer Nanocomposites

Significantly enhanced dielectric constant and energy storage density positively facilitate miniaturising dielectric capacitors for various applications in electronics and electrical devices. Herein, a fluoropolymer is coated on BaTiO 3 (BT) nanoparticles to form a core–shell structure (BT@PF80), which is used as additional dipoles to enhance the dielectric constant and energy density of polymer nanocomposites. Characterizations with various techniques show uniform dispersion of nanoparticles and good compatibility of interfaces in polymer nanocomposites. Furthermore, the dielectric constant increases from 7.85 of neat polymer to 9.43 of the nanocomposites filled with BT@PF80 while the dielectric loss further decreases from 0.05 to 0.04 at 1 KHz. In addition, 7.79 J cm −3 of energy density is achieved at the nanocomposites filled with BT@PF80, which is 2.65 times higher than that of the neat polymer. This work presents a simple and effective means to enhance dielectric constant and energy density, which tends to fertilize the fabrications of polymer dielectrics for electric energy storage.