CeO₂/ZnO-based photocatalytic materials were synthesized by the sol-gel method in order to establish heterojunctions that increase the degradation efficiency of some types of antibiotics by preventing the recombination of electron–hole pairs. The synthesized materials were analysed by XRD, SEM, EDAX, FTIR, and UV-Vis. After several tests, the optimal concentration of the catalyst was determined to be 0.05 g‧L⁻¹ and 0.025 g‧L⁻¹ for chlortetracycline and 0.05 g‧L⁻¹ for ceftriaxone. CeO₂/ZnO assemblies showed much better degradation efficiency compared to ZnO or CeO₂ tested individually. Sample S3 shows good photocatalytic properties for the elimination of ceftriaxone and tetracycline both from single solutions and from the binary solution. This work provides a different perspective to identify other powerful and inexpensive photocatalysts for wastewater treatment.

This article reports on a new way of valorizing vine leaves waste as a renewable resource of polyphenols. The nanoparticles containing zinc complexes were prepared by a green synthesis method using the aqueous extract of vine leaves as a natural source of ligands for the complexation of zinc ions. The prepared nanoparticles were characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) in conjunction with energy dispersive X-ray spectroscopy (EDX). Another objective of this study was to obtain a cream into which the biosynthesized nanoparticles would be incorporated. In the formulation of the new cream, we aimed to use the minimal required amounts of synthetic emulsifiers and to use natural products as co-emulsifiers or as viscosity modifiers. The organoleptic characteristics and the physicochemical properties of the obtained creams were evaluated. The experimental results confirmed that the creams wherein the nanoparticles containing zinc complexes were incorporated exhibited antimicrobial activity against the bacterial species Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Escherichia coli and the yeast Candida albicans. The values obtained for pH, viscosity and spreading diameter of the creams produced indicate that these formulations are suitable for topical applications.