ZnO/ZrO₂ composites: synthesis characterization and photocatalytic performance in the degradation of oxytetracycline antibiotic

Abstract

ZnO/ZrO2 composite catalysts of different morphologies were synthesized by co-precipitation method and then characterized by SEM (Scanning Electron Microscope), XRD (X-ray Diffraction), PL (Photoluminescence), UV-vis DRS (Diffuse Reflectance Spectra). The surface properties were obtained using BET advanced analytical technique. The synthesized catalysts were analyzed to determine the photocatalytic efficiency using oxytetracycline (OTC) antibiotic under UV light. ZnO/ZrO2 with mole ratio 0.5:1 exhibited higher photocatalytic activity under optimal conditions that can be attributed to the effective inhibition of e−/h+ recombination. The optimal experimental conditions were setup at pH 5 with catalyst dosage of 24 g∙L−1 and at initial OTC concentration of 10 mg∙L−1. The carbonate, nitrate and iodate ions (CO32−, NO3−, IO3−)were used to evaluate possible degradation mechanism. The IO3− ions were found more active in the photocatalytic degradation mechanism.