Study of the structural, optical and electrical properties of PVA/SA performance by incorporating Al₂O₃ nanoparticles

Aluminum oxide nanoparticles (Al₂O₃ NPs) were added to polyvinylpyrrolidone (PVP) and sodium alginate (SA) blend to synthesis nanocomposite films, using a solution casting technique, with favorable optical and electrical properties. The results reveal a series of noteworthy findings, where X-ray diffraction (XRD) measurement also shows that the addition of Al₂O₃ NPs to PVP/SA blend caused a decrease in the crystallinity of the filled samples. Fourier infrared (FTIR) analysis showed prominent characteristic peaks corresponding to vibrational groups characterizing the prepared nanocomposite samples, which change randomly with increasing concentration of Al₂O₃ NPs. Moreover, the indirect/direct optical energy gap decreased from 3.96/5.28 to 2.73/3.59 eV at 2.0 wt% of Al₂O₃ NPs, confirming the improvement in the optical features of the doped samples, as evidenced by UV/Vis spectra. After adding the nanoparticles to the blend, AC electrical conductivity increased and showed to follows Jonscher’s rule. The maximum value of AC conductivity observed at 2.0 wt% of Al₂O₃ NPs in the blend is 1.445 \(\times\) 10^− 6 S/cm. Additionally, the addition of the nanoparticles has been shown to increase in dielectric loss and dielectric constant of the composite samples. The improvement of the optical and electrical properties due to filling with Al₂O₃ NPs indicates the possibility of using the prepared nanocomposites in optoelectronic devices. Also, studying the effect of incorporating Al₂O₃ nanoparticles into PVP/SA blends has attracted little attention in the literature; therefore, this study is considered as a new research one.