Enhancement of antibacterial activities of green synthesized-CuO/ZnO nanocomposites using <i>Boehmeria nivea</i> leaf extract

This study investigated CuO and ZnO nanoparticles and CuO/ZnO nanocomposites in a friendly environment with a low-cost and renewable biosynthesis method. This approach involved using Boehmeria nivea leaf extract to facilitate the growth and formation of nanocomposites with performance-enhancing phytochemicals released during the co-precipitation process. All nanoparticles/nanocomposites explored the microstructure, morphology, and point defects using FTIR, XRD, SEM, and PL characterization techniques. The synthesized CuO and ZnO nanoparticles and CuO/ZnO nanocomposites were evaluated for their antibacterial ability against both bacteria Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Combining different copper and zinc salt ratios creates different arrangements and morphologies between the CuO sheets and the spherical ZnO nanoparticles. The heterojunction of CuO/ZnO samples enhances the antibacterial effects of nanocomposites compared to pure CuO and ZnO nanoparticles. The maximum antibacterial performance was achieved at 250 ppm against E. coli and 500 ppm against S. aureus in CuO50/ZnO50 nanocomposites. This study shows that a green synthesis of CuO/ZnO nanocomposites promises great potential for environmental treatment and biochemical applications.