Synthesis of Spherical Copper Oxide Nanoparticles by Chemical Precipitation Method and Investigation of Their Photocatalytic and Antibacterial Activities

Methylene blue (MB) dye and Staphylococcus aureus (S. aureus) bacteria in wastewater are the two significant problems currently. Researchers have been looking for materials that can combat these two problems at the same time. In the present study, we describe the synthesis of spherical copper oxide (CuO) nanoparticles (NPs) by the chemical precipitation method and evaluate their photocatalytic performance against MB dye and antibacterial efficacy against S. aureus. CuO NPs were produced using copper acetate monohydrate (Cu(CH3COO)2·H2O) as the precursor and sodium hydroxide (NaOH) as the reducing agent. Synthesized CuO NPs were characterized using a combination of techniques, including ultraviolet–visible spectroscopy, X-ray diffraction, transmission electron microscopy, selected area electron diffraction, Fourier transform infrared, and energy-dispersive X-ray diffraction analysis. All the analyses indicated that monoclinic CuO NPs were formed with a spherical shape and an average particle size of 6.2 nm. Photocatalytic experiments indicated that 55.5% of a 10 ppm MB dye solution was degraded by the prepared nano-CuO photocatalyst only after 60 min. Additionally, synthesized CuO NPs demonstrated, to some extent, the zone of inhibition on the S. aureus bacterium’s cell wall. It is inspiring that CuO NPs can be used to solve two problems of MB dye contamination and S. aureus bacterial infection simultaneously.