Synthesis, Characterization, and Antimicrobial Activity of CoO Nanoparticles from a Co (II) Complex Derived from Polyvinyl Alcohol and Aminobenzoic Acid Derivative

Cobalt oxide nanoparticles (CoO NPs) were synthesized by the calcination method from the Co (II) complex which has the formula [Co(PVA)( P -ABA)(H 2 O) 3 ], PVA = polyvinyl alcohol, and P -ABA =  para -aminobenzoic acid. The calcination temperature was 550°C, and the products were characterized by element analysis, thermal analyses (TGA and DTA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV-Vis spectra, and scanning electron microscopy (SEM) techniques. The kinetic and thermodynamic parameters (∆H  ∗ , ∆G  ∗ , and ∆S  ∗ ) for the cobalt (II) complex are calculated. The charges been carried by the atoms cause dipole moment 10.53 and 3.84 debye and total energy 11.04 × 10 2 and 24.80 × 10 2 k Cal mol −1 for the Co (II) complex and cobalt oxide, respectively. X-ray diffraction confirmed that the resulting oxide was pure single-crystalline CoO nanoparticles. Scanning electron microscopy indicating that the crystallite size of cobalt oxide nanocrystals was in the range of 36–54 nm. Finally, the antimicrobial activity of cobalt oxide nanoparticles was evaluated using four bacterial strains and one fungal strain. Two strains of Gram-positive cocci ( Staphylococcus aureus and Enterococcus faecalis ), two strains of Gram-negative bacilli ( Escherichia coli and Pseudomonas aeruginosa ), and one strain of yeast such as fungi ( Candida albicans ) were used in this study.