Polymer Based ZnO–SiO 2 Nanocomposite Flexible Sheets as High Dielectric Materials

Flexible dielectric polymer nanocomposites (NCs) with high dielectric permittivity and low loss factor have numerous applications in light emitting and storage devices. In this research work, polymer based NCs in the form of flexible sheets containing 5% ZnO and 15, 20% SiO2 nano-fillers, are synthesized by using co-precipitation method. X-ray diffraction analysis reveals the development of various diffraction planes related to ZnO and SiO2 phases confirms the synthesis of polycrystalline PB–ZnO–SiO2 NCs flexible sheets corresponding to various compositions. Morphology and compositional analysis show the uniform distribution of nanoparticles in polymer matrix with estimated elemental contents in each composition. Dielectric measurements demonstrate a sharp increase in dielectric permittivity with relatively low dissipation factor in synthesized compositions having ZnO and SiO2 nano-fillers. The static value of dielectric constant at 100 Hz is found to be 10.79 for sample having 20% SiO2 nano-fillers that is 3.4 times greater than pure PVA and it shows relatively low value of dissipation factor. The observed AC conductivity of synthesized NCs flexible sheets having 5% ZnO, 20% SiO2 nano-fillers is 2.15 × 10–5 S/m that is 3.3 times greater than pure PVA at 1 × 106 Hz. Complex impedance spectroscopy further confirms, these materials as promising candidates for better capacitive performance.