LAUSR

Abstract Copper oxide particles have found applications as strong photocatalytic antibacterial agents in recent years. This paper investigates the facile chemical bath deposition synthesis and antibacterial properties of nanocrystalline CuO, CuO-GO, and CuO-GO-Ag nanocomposites. CuO samples were synthesized through a chemical bath deposition method and the introduction of GO nanosheets and silver nanoparticles into the precursor solutions was used to obtain CuO-GO and CuO-GO-Ag nanocomposites. Scanning electron microscope, energy dispersive spectroscopy, elemental mapping, and Fourier-transform infrared spectroscopy were used to characterize synthesized specimens. Antibacterial properties of the nanocomposites were examined against Gram-positive Staphylococcus aureus ATCC 25923 and Gram-negative Escherichia coli ATCC 25922 by the disc diffusion method and minimum inhibitory concentration (MIC) measurements. CuO particles with monoclinic crystallographic structure and crystallite size of 10 nm were synthesized. Synthesized particles were spherical with a narrow size distribution, between 5 and 10 μm. Minor addition of GO to the precursor solution resulted in less agglomeration of nanocomposite powders. CuO-GO-Ag nanocomposite showed noticeable enhanced antibacterial activities against the tested bacteria under visible light, resulting in MIC of 2.6 ± 0.5 mg/ml against Gram-positive and Gram-negative bacteria and also higher inhabitation zone compared to CuO and CuO-GO nanocomposites.