Enhanced photocatalytic efficiencies in a bifunctional ZnO/PVA nanocomposites derived from Capparis zeylanica L.

The modern food sector demands versatile nanocomposites of polymers for food to wrappers to inactivate germs linked to foods in order to ensure quality throughout the packaging process. Recently, it has become quite appealing to use zinc oxide nanocomposite with polyvinyl alcohol (PVA) assistance for food storage containers. Variable combinations of zinc acetate and Capparis zeylanica leaf extract (3:1, 1:7, 1:3, and 1:1) were used to create nanostructured ZnO at the desired pH (10.5). ZnO/PVA nanocomposites films were created with different weight % of (16, 13, 9 and 5%) ZnO nanoparticles by using solution casting method. The generated ZnO and ZnO/PVA nanocomposites (NCs) were characterized using analytical techniques like X-ray diffraction spectroscopy (XRD), ultraviolet spectroscopic analysis (UV-Vis), Fourier-transform infrared analysis (FT-IR), and field emission scanning electron microscopic study (FE-SEM). The generated ZnO and ZnO/PVA NCs were tested for their efficacy as antibacterial agents against Gram + ve (Streptococcus pyogenes, Staphylococcus aureus) and Gram -ve (Pseudomonas aeruginosa, and E. coli) bacteria. Under UV-visible irradiation, the methylene blue (MB) breakdown caused by the fabricated undoped ZnO and ZnO/PVA nanomixture was investigated. The FE-SEM investigation for synthesized ZnO from a 1:1 ratio exhibited spherical shaped appearance. However, the nanocomposite made with 5% ZnO showed equally scattered nanoflake particles in the matrix of PVA film as well as on the surface. The XRD results showed that ZnO synthesized with a higher proportion of plant extract produced smaller crystallites, whereas ZnO synthesized with a lower percentage of plant extract produced bigger crystallite sizes. The optimum concentration for the breakdown of methylene blue (MB) among the various concentrations examined was 5% ZnO/PVA. Furthermore, a study of the biomedical efficiency of undoped ZnO and ZnO/PVA revealed that 5% ZnO/PVA had the potential antibacterial efficacies.

Smart apparel using nano graphitic carbon nitride/PVA in a cotton cloth for military application.

An eco-friendly, low-cost smart attire was made of metal-free graphitic carbon nitride (GCN) as a semiconductor material in a biodegradable synthetic polymer (polyvinyl alcohol) and cotton material. Various concentrations such as 0.04, 0.08, 0.12, 0.16, and 0.2 weight percentage of GCN is entrenched in PVA. UV absorption spectra displayed two peaks, one matching PVA (317 nm) and the other excitonic peak of GCN (390 nm).0.2% GCN in PVA showed a low bandgap (2.84 eV) harnessing maximum solar light. Due to the charge transfer mechanism, enhanced blue emission at 450 nm was observed for the higher concentration of graphitic carbon nitride. Due to more defect centers of higher weight percentage of GCN, higher electrical conductivity (7.6462 × 10-3 S/cm) and optical conductivity (0.113 S) were noticed. Due to the higher conductivity of 5GCN, it was embedded with cotton fabric. The fabricated smart apparel can be used to manufacture flexible, lightweight, eco-friendly optoelectronic devices. Further, according to literature, GCN possesses high antibacterial activity, hence it can serve as clothing for the military and medical community.