Nanoarchitectonics of Octahedral Co 3 O 4 /Chitosan Composite for Photo-Catalytic Degradation of Methylene Blue and Anti-Bacterial Activity

The octahedron-shaped spinel cobalt oxide micro-particles (Co 3 O 4 MPs) are fabricated via the thermal decomposition of a new cobalt(III) complex precursor without employing toxic solvents, surfactants, and complicated equipment. The X-ray structure of the precursor consists of one non-coordinating chloride anion and one mononuclear cation [Co(L) 2 ] + of the CoN 4 O 2 structure with Co(III) center adopting a distorted octahedral geometry. The octahedral Co 3 O 4 MPs are decorated on the chitosan (CS) polymer to form a Co 3 O 4 @CS composite. The chemical composition, phase structure, morphology, band gap energy, and magnetic properties of the samples are studied using the FT-IR, EDX, XRD, FE-SEM, AFM, UV–visible DRS, and VSM techniques. The Co 3 O 4 -catalyzed methylene blue (MB) degradation under LED light is investigated, and the operating conditions are optimized. Then the performance of the chitosan-decorated Co 3 O 4 MPs is evaluated in the photo-degradation of MB at the optimum conditions. The kinetics mechanism and reusability of the catalysts are studied. Moreover, the anti-bacterial activity of the prepared samples is tested against the Gram + ve and Gram −ve bacterial strains.