Cobalt oxide nanoparticles for biological applications: Synthesis and physicochemical characteristics for different natural fuels.

Cobalt oxide (Co 3 O 4) nanoparticles were synthesized via a simple combustion process employing natural fuels, and their structural, morphological, thermal, and antibacterial properties were studied. According to XRD measurements, each specimen has a cubic crystalline structure. Co 3 O 4 nanoparticles prepared from natural macromolecules such as cow urine, honey, wine, and tea extract had respective crystallite diameters of 22.9, 31.3, 30.4, and 31.2 nm. According to FESEM and EDAX analyses, the products have stoichiometric shapes such as rice grains, mushrooms, and cluster cavities, and EDX confirmed the presence of the Co and O elements. The FTIR image revealed the presence of various phytochemicals on the surface, and the bands at 400 and 630 cm−1 denoted the distinctive Co–O linkages. The diameters of crystallites and TEM particles are comparable. The thermal properties of Co 3 O 4 nanoparticles synthesized with diverse natural fuels are characterized by substantial weight losses. The particle's colloidal stability has been investigated. It confirms that the use of natural resources influences particle stability. Antibacterial and antifungal activity of green synthesized Co 3 O 4 nanoparticles was evaluated against two distinct bacteria (Gram-positive) Staphylococcus aureus and (Gram-negative) Pseudomonas aeruginosa, as well as two fungi, Candida albicans and Aspergillus niger. It has been discovered that synthetic Co 3 O 4 nanoparticles inhibit microbial and fungal proliferation effectively. [ABSTRACT FROM AUTHOR]