Enhancing and modifying the optical, magnetic, and electrical features of PVA&PVP; composite filled with ZnFe₂O₄ nanoparticles for magneto-optical applications

Abstract This research employed a sol–gel method to synthesize zinc ferrite nanoparticles (ZnFe 2 O 4 NPs). These nanoparticles were then dispersed within a blend of polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) (with a weight ratio of 50:50) to fabricate polymer nanocomposite samples (PNCSs) via a solution casting technique. The XRD patterns suggest significant structural alterations in the nanocomposite compared to the pure polymer blend, which is evident in changes in crystallinity and cluster size (D). At the same time, the atomic arrangement within the material remains unaffected (d spacing). The FTIR absorption spectra were analyzed to assess the miscibility of PVA and PVP, as well as their interactions with the ZnFe 2 O 4 NPs. The presence of characteristic peaks for both polymers without significant shifting suggested good miscibility. The optical bandgap of the nanocomposite samples decreases from 4.79 to 3.16 eV, and the absorption edge gradually shifts toward longer wavelengths with the addition of ZnFe 2 O 4 NPs. Thermal analysis using TGA was also conducted to investigate how the samples decompose with increasing temperature. Coats-Redfern and Broido models were also used to study the activation energy. The magnetic properties of the PVA/PVP-ZnFe 2 O 4 nanocomposites were assessed using the VSM technique at room temperature, revealing ferromagnetic behavior with a significant increase in saturation magnetization (Ms), remanent magnetization (Mr), and loop area (La) as the ZnFe 2 O 4 content increased. Across the frequency range of 0.1 Hz to 10 MHz, the PVA/PVP-ZnFe 2 O 4 NP samples exhibited significantly improved electrical conductivity and dielectric properties. In addition, the dielectric properties and electric modulus of these PNCSs were studied, where the ZnFe 2 O 4 NPs successfully improved the host matrix’s capacity for storing energy. As a result, these interesting physicochemical characteristics show how well these PNCSs are suited for use in flexible-type micro- and optoelectronic methods, such as nanodielectric substrates, light diffusers, bandgap regulators, photosensors, and UV shielders.