ZnO nanoparticles-tailored GO dispersion toward flexible dielectric composites with high relative permittivity, low dielectric loss and high breakdown strength

Zinc oxide (ZnO) nanoparticles and graphene oxide (GO) nanosheets are self-assembled to form the hybrid ZnO@GO nanoparticles through the simple solution compounding processing with the aid of ultrasonic treatment. There is a good interaction between ZnO and GO, which promotes the deposition of ZnO nanoparticles on the surface of GO nanosheets and the exfoliation of GO nanosheets. Microstructure and morphology characterizations of the poly(vinylidene fluoride) (PVDF)-based composites show that the PVDF/ZnO@GO composites exhibit largely improved dispersion of fillers compared with the PVDF/GO composites. At high filler content, ZnO@GO nanoparticles also induce the change of α-form to β-form PVDF. The hybrid ZnO@GO nanoparticles endow the composites with high relative permittivity, low dielectric loss and high breakdown strength . Furthermore, the composite samples also show good flexibility. This work confirms that incorporating the hybrid nanoparticles that are composed of semi-conductive fillers is an efficient way to prepare the dielectric composites with promising properties.