The preparation of poly (vinyl alcohol)/chitosan/ZnO (PVA/Cs/ZnO) nanocomposite films as bioactive nanocomposites was implemented through an environmentally friendly approach that included mixing, solution pouring, and solvent evaporation. The nanocomposite films were characterized using various techniques such as X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and UV-Vis spectroscopy. The XRD study revealed the encapsulation of nanoparticles by the PVA/Cs blend matrix. The DSC results showed that the addition of ZnO NPs increased glass transition and melting temperature values of the PVA/Cs blend. ATR-FTIR spectra detected an irregular shift (either red or blue) in some of the characteristic bands of the PVA/Cs nanocomposite, indicating the existence of intra/intermolecular hydrogen bonding creating an interaction between the OH groups of PVA/Cs and ZnO nanoparticles. A thermogravimetric (TGA) analysis demonstrated that the nanocomposites achieved better thermal resistance than a pure PVA/Cs blend and its thermal stability was enhanced with increasing concentration of ZnO nanoparticles. UV analysis showed that with an increase in the content of ZnO NPs, the optical bandgap of PVA/Cs was decreased from 4.43 eV to 3.55 eV and linear and nonlinear parameters were enhanced. Our optical results suggest the use of PVA/Cs/ZnO nanocomposite films for various optoelectronics applications. PVA/Cs/ZnO nanocomposites exhibited significant antibacterial activity against Gram-positive and Gram-negative bacteria. It was found that nanocomposite samples were more effective against Gram-positive compared to Gram-negative bacteria.

Polyvinyl alcohol (PVA) and Neodymium (III) oxide (Nd₂O₃) were combined to synthesized flexible innovative PVA/Nd₂O₃ polymer composite samples utilizing a solution casting approach for use in dielectric devices. The XRD, FTIR, and SEM methods are all investigated to characterize the composite films. In a frequency of 50 Hz to 5 MHz, the effects of additive Nd₂O₃ on the dielectric behavior of PVA were recorded. The PVA/Nd₂O₃ composite films were successfully fabricated, as shown by XRD and infrared spectroscopy. The scanning microscopy pictures showed that the Nd₂O₃ was loaded and distributed uniformly throughout the PVA. After the incorporation of Nd₂O₃, the composite PVA/Nd₂O₃ has a conductivity of 6.82 $\times$ 10⁻⁹ S·cm⁻¹, while the PVA has a conductivity of 0.82 $\times$ 10⁻⁹ S·cm⁻¹. Another improvement is the decrease in the relaxation time from 14.2 $\times$ 10⁻⁵ s for PVA to 6.35 $\times$ 10⁻⁵ s for PVA/Nd₂O₃, and an increase in the dielectric constant of 0.237 for PVA to 0.484 at a frequency of 100 Hz. The results showed that the composite samples have considerable changes as flexible films in different applications, including batteries and electronic circuits.

Two forms of flower-like ZnO nanostructures were synthesized using hydrothermal methods at various growth times/temperatures and zinc precursors. The morphology, structure, chemical composition, and optical properties of these ZnO nanoflowers were studied using a scanning electron microscope (SEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectrons spectroscopy (XPS), Raman spectroscopy, and UV–Vis spectroscopy. The SEM images revealed two forms of flower-like nanostructures, namely lotus- and tulip-like flower ZnO nanostructures. The XPS analysis revealed the oxidation state of the Zn and O elements, as well as the presence of OH groups on the surface of the lotus-like flower ZnO nanostructure. The XRD results revealed less crystallinity of the lotus-like ZnO nanoflowers (NFs) compared with the tulip-like ZnO NFs. The XRD results revealed the presence of Zn (OH)₂ in the ZnO NFs. The Raman results confirmed less crystallinity of the lotus-like ZnO NFs. The estimated optical bandgap was 2.92 and 3.0 eV for the tulip- and lotus-like ZnO NFs, respectively. The tulip-like ZnO NFs showed superior photocatalytic degradation of methylene blue dye, verified via UV–Vis radiation, compared with the lotus-like ZnO NFs, which show the impact of the structure defects and OH- impurities on the photocatalytic performance of ZnO nanoflowers.