Structural and optical properties of polymer blend nanocomposites based on PVP/PVA incorporated AgNO3

In this study, polymer nanocomposite based on polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), and silver nitrate (AgNO3) has been prepared through chemical reduction rate and casting method for varying concentrations of AgNO3. The PVP/PVA blend consisted of 0.6 wt.% PVP and 0.4 wt.% PVA. Following that, polymer nanocomposites were prepared by incorporating different concentrations of AgNO3 (0, 10, 20, 30, 40, and 50 wt.%) into the polymer blend. The effects of different concentrations of AgNO3 on the structural and optical properties of the PVP/PVA blend were investigated using X-ray diffraction (XRD) and UV-Vis absorption spectroscopy. The XRD analysis demonstrated that increasing the concentration of AgNO3 results in a decrease in the degree of crystallinity from 53.73 in the PVP/PVA blend to 15.77 in the PVP/PVA nanocomposite containing 50 wt.% AgNO3. UV-Vis absorbance spectra were examined to determine optical properties such as the absorption coefficient, absorption edge, optical band gap, and tails of localized states. The results revealed that the increase in AgNO3 concentrations caused a reduction in the absorption edge and optical band gap, alongside an increase in Urbach energy.