Facile Synthesis of Cobalt Oxide Nanoparticles via Galvanostatic Deposition: Characterization and Their Antibacterial and Antifungal Activities

Cobalt oxide nanoparticles (Co3O4 NPs) exhibit a variety of biomedical applications due to their special antioxidant, antibacterial, antifungal, anticancer, healing of wounds, and anti-diabetic characteristics. This work successfully prepared the Co3O4 NPs via simple galvanostatic deposition followed by annealing at 400 and 800oC for two hours. The galvanostatic deposition was carried out from a modified Watts bath. We used Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) to examine the oxide's characterization properties. The nature of the oxide formed was strongly dependent on the annealing temperature. The powder formed at room temperature (25oC) is a mixture of Co(OH)2 and metallic Co. However, at 400 and 800oC, and according to the XRD patterns, the powder is primarily composed of the Co3O4 phase and a slight quantity of Co(OH)2 phase. The average particle size measured by TEM ranged from 14.85 nm at room temperature to 90.19 nm at 800 oC. Moreover, the study examined how the operating deposition parameters affected the galvanostatic deposition process. Furthermore, these baths produce NPs, a great antibacterial agent that fights a variety of gram-positive and gram-negative bacteria, especially Staphylococcus aureus and Escherichia coli in addition to their effectiveness in terms of antifungal activity.