An efficient biosynthesis of novel ZnO/CuO nanocomposites using berberis vulgaris extract (ZnO/CuO@BVENCs) for enhanced photocatalytic degradation of pollution, antibacterial and antifungal activity

Abstract

In this study, an environmentally-friendly method was employed to synthesize ZnO/CuO nanocomposites using berberis vulgaris extract, resulting in ZnO/CuO@BVE NCs. The structure and properties of the ZnO/CuO@BVE NCs were characterized using various analytical techniques including XRD, UV-DRS, FESEM, FT-IR, EDAX, and TEM. UV-DRS results highlighted a bandgap energy reduction from 3.11 eV to 2.93 eV due to CuO integration with ZnO. TEM images confirmed the nanocomposite size to be between 35–50 nm. To evaluate the photocatalytic effectiveness of the biosynthesized nanocomposites, rhodamine b (RhB) was used as a representative contaminant. We thoroughly investigated the influence of multiple variables such as dye concentration, nanocatalyst amount, light source, and pH on the photocatalytic degradation of RhB. Under optimized conditions (0.15 g/L nanocatalyst, pH 11, UV light, and 3 ppm pollutant concentration), a remarkable 97.3% RhB degradation efficiency was achieved. Additionally, the antibacterial properties of the ZnO/CuO@BVE NCs were tested against six ATCC strains. Notably, they exhibited strong antibacterial action, especially against K. pneumoniae and P. aeruginosa, with a minimum inhibitory concentration (MIC) as low as 62.5 μg/mL. Furthermore, the nanocomposites demonstrated significant antifungal activity against C. albicans with an MIC of 31.2μg/mL. This research emphasizes the potential applications of ZnO/CuO@BVE NCs in environmental remediation and medical fields.