Incorporating hybrid Ag/Co2O3 nanofillers into PVP/CS blends for multifunctional optoelectronic and nanodielectric applications

Abstract

This study involves the creation of nanocomposites using an organic polymeric blend of polyvinyl pyrrolidone (PVP) and chitosan (CS) in a 70/30 wt% ratio. These nanocomposites incorporate silver and cobalt oxide nanoparticles (Ag/(x)Co2O3 NPs) (x = 0.20, 0.5 and 1.0 wt%). The fabrication process employs a solution-casting method. The study investigates how Ag/(x)Co2O3 nanoparticles affect the structural properties of pure PVP/CS through the application of various analytical techniques. The XRD findings indicate that the PVP/CS polymer blend is amorphous, and they confirm the incorporation of Ag/(x)Co2O3 nanoparticles into its structure. Additionally, FT-IR analysis indicates the presence of an electrostatic interaction between the PVP/CS polymeric matrix and Ag/(x)Co2O3 nanoparticles, resulting in the formation of metal oxides/polymer complexes. As the concentration of cobalt oxide nanoparticles within the host matrix (PVP/CS) increases, the optical properties of the synthesized PVP/CS-Ag/(x)Co2O3 nanocomposites, including both direct and indirect bandgap energies, show a decreasing trend. The TGA analysis demonstrates an improvement in the thermal stability of the samples upon the incorporation of Ag/(x)Co2O3. Moreover, the activation energy was calculated by analyzing the TGA curves, employing both the Coats–Redfern and Broido methods. The inclusion of Ag/(x)Co2O3 nanoparticles in the PVP/CS host matrix enhances the charge conduction mechanism, as shown by the significantly higher conductivity results (σ) observed in the doped films. The synthesized PVP/CS-Ag/(x)Co2O3 nanocomposite exhibits favorable optical, thermal, and electrical conductivity properties, making it a promising candidate for applications in optoelectronic devices and energy storage, particularly in the context of thin film supercapacitors.