Improved dielectric properties and energy-storage densities of BaTiO3-doped PVDF composites by heat treatment and surface modification of BaTiO3

Abstract In this paper, the dielectric properties of barium titanate/polyvinylidene fluoride (BT/PVDF) composites are investigated. The doped BT particles were prepared using a simple heat treatment. It was found that 1000 °C was the optimal temperature for the doped BT particles to improve the dielectric properties of the BT/PVDF composites. Furthermore, we also found that the breakdown strength of the BT/PVDF composites could be significantly enhanced when the surface of the doped BT particles were pre-modified with phthalic acid or KH550. In particular, the BT/PVDF composites doped with KH550-modified BT particles had a maximum energy-storage density of 4.08 J cm −3 , which is 81.33% higher than that of BT/PVDF composites doped with BT particles and without any treatment. Therefore, we can conclude that heat treatment and surface modification of doped BT particles could become a new approach to enhance the energy-storage performance of BT/PVDF composites, and which has good application prospects in the field of dielectric energy-storage materials.