Antibacterial Application of Heterogeneous CuO-NiO-ZnO Metal Oxides Nanocomposites

Abstract The synthesis, characterization, & use of mixed metal oxides, a unique family of compounds, have attracted ever-increasing interest as they offer an excellent opportunity to refine the desired properties for improved functional performance in interaction with base metal oxides. In this study, NiO-ZnO-CuO composites are synthesized by using simple co-precipitation technique at 200oC and 500oC temperature and then characterized for its properties by UV-visible, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) studies, Dynamic Light Scattering (DLS) and Scanning electron microscopy (SEM) analysis. At 200°C & 500°C, the CuO-NiO-ZnO nanocomposite had an optical band gap energy of 2.70 eV & 2.67 eV, respectively. The UV-visible spectroscopy was utilized to find the band gap using the Tauc plot. XRD studies indicated the presence of well-defined CuO (monoclinic), NiO (cubic), & ZnO (hexagonal) phases, with the maximum fraction of volume belonging to the NiO. The images of SEM by mixed oxide nanocomposites display nanoparticles in the form of irregular shapes. The phases indicate the presence of trimetallic oxide heterojunctions, which strongly impact the overall properties of nanocomposites (NCs). Also, the antibacterial activities of nanocomposites are studied, which showed that at 200°C, the nanocomposite exhibited antibacterial action against gram-negative bacteria (GNB), whereas at 500°C, it demonstrated efficacy against gram-positive bacteria (GPB) and also affected GPB at higher doses.