Exploring Nano-sulfide Enhancements on the Optical, Structural and Thermal Properties of Polymeric Nanocomposites

Copper sulfide (CuS) nanoparticles were synthesized by solid-state reaction method under the flow of nitrogen. Polyvinyl alcohol/polyethylene glycol/copper sulfide (PVA/PEG:CuS) nanocomposite films with different concentrations of copper sulfide nanoparticles (1%, 3%, 5%) were prepared using casting technique. Structural and morphological properties of the prepared nano samples were investigated using X-ray diffraction data (XRD), transmission electron microscope and energy dispersive spectrometry techniques. The formation of nanocomposite films was confirmed by both XRD and fourier transform infrared techniques. Calculated and measured nano material particle size is almost similar. The characteristic peaks of nanocomposite films were found to be shifted towards higher wavenumber. The thermal stability behavior of row (PVA/PEG) blends and (PVA/PEG:CuS) nanocomposite films was examined using the thermogravimetric analysis technique. Samples doped with 5% CuS concentration revealed the highest thermal stability. The optical properties of undoped and nanocomposite films have been discussed in details using UV-Vis spectrophotometer. The optical transmittance revealed an apparent decrease (more than 40% for films doped 5% CuS). Different optical constants and dispersion parameters were discussed in detail and proved to be directly affected by nano doping concentrations. The optical energy gap values of polymer films decreased from 5.3 to 3.3 eV with the CuS nanoparticles incorporation. The study of the PVA/PEG nanocomposite films based on CuS nanoparticles has not been previously discussed. Therefore, this study is considered a new piece of work.