Enhanced thermal and dielectric performance in ternary $PVDF/PVP/Co_3O_4$ nanocomposites

Abstract

The main objective of this research was to prepare high thermal and dielectric performance $PVDF/PVP/Co_3O_4$ nanocomposites (PVDF, oply(vinylidene fluoride); PVP, polyvinylpyrrolidone) using the method of solution mixing. The structural properties and thermal stability of the samples were examined through measurements of XRD, SEM, Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). From the XRD measurements, the cubic crystal structure of the $Co_3O_4$ nanoparticles was revealed with an average size of 17 nm. Also, diffraction peaks of the α-phase were seen in $PVDF/PVP/Co_3O_4$ nanocomposite spectra. The SEM images for the surface of the films showed a homogeneous distribution of the nanoparticles. The absorption peaks of both α- and β-phases were confirmed by measurements of the FTIR spectra. The nanocomposite films grafted with $Co_3O_4$ nanoparticles possess high thermal stability. The dielectric permittivity and energy density of the nanocomposites improved significantly at 4.0 wt% $Co_3O_4$. Finally, the increase in $Co_3O_4$ content caused an improvement in dielectric response function as well as electrical conductivity.