Dielectric properties of polyvinyl alcohol (PVA) nanocomposites filled with green synthesized zinc sulphide (ZnS) nanoparticles

In this study, zinc sulphide nanoparticles (ZnS NPs) have been synthesized by green synthesis approach. These ZnS NPs were used as nanofiller to fabricate polyvinyl alcohol (PVA) based nanocomposite films via solution casting method. The PVA/ZnS nanocomposite films have been characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy and thermogravimetric analysis. The results from these characterization techniques evidenced the improvement in structural, morphological and thermal properties of PVA/ZnS nanocomposite films and also confirmed the incorporation of ZnS NPs in the PVA matrix. In addition to that, the dielectric properties of the PVA/ZnS nanocomposite films were investigated for different frequencies (50 Hz–1 MHz) and temperatures (40–140 °C) using an impedance analyzer. The values of dielectric constant and dielectric loss of PVA/ZnS nanocomposite films were observed to be 328.93 (50 Hz, 140 °C) and 6.02 (50 Hz, 140 °C) with 3 wt% ZnS NPs content. This enhancement in dielectric properties demonstrated the good interaction between ZnS NPs and PVA matrix. The aforementioned results evidenced that the ZnS NPs were homogeneously distributed within the PVA matrix.