Improved energy density and dielectric properties of P(VDF-HFP) composites with TiO2 nanowire clusters

Dielectric composites are of great demand in the micro-electronics industry. To enhance the energy storage density of the composites, TiO 2 nanowire clusters was synthesized by a hydrothermal method and incorporated into the P(VDF-HFP) polymer matrix in this work. The microstructure, dielectric properties of the prepared film were discussed and the effects of TiO 2 loading on the energy density were investigated. The results shows that the TiO 2 clusters were tightly blended to the P(VDF-HFP) matrix owing to the dopamine-modified interface. The dielectric constant increased with the loading of TiO 2 , the maximum dielectric constant reached 12.04 with 7.5 vol% TiO 2 loading at 1 kHz, as compared to 5.01 for the neat P(VDF-HFP). The enhanced dielectric constant was attributed to the interface polarization originated from the large interface area between the TiO 2 nanowire and polymer matrix. The discharged energy density of the composite significantly increased to 1.35 J/cm 3 with 7.5 vol% TiO 2 nanowire clusters, which was two times higher than that of the neat P(VDF-HFP) at the same condition. The findings of this work can shed a light on improving the energy density of energy storage device via morphology modification.