Facile Fabrication of Co3O4 Nanostructures as an Effective Photocatalyst for Degradation and Removal of Organic Contaminants

Co3O4 nanoparticles were synthesized via a simple Co-precipitation reaction between precursors of cobalt and NH3. The effect of different parameters such as concentration of NH3 and precursors of cobalt on the size and photocatalytic activity of the products was investigated. The achieved nanoparticles were characterized by X-ray powder diffraction analysis, field emission scanning electron microscopy, energy-dispersive spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). The photocatalytic behavior of Co3O4 nanoparticles was evaluated using the degradation of various organic pollutants (rothamine B and methyl orange) under visible irradiation. Also effect of pH on the photocatalytic performance of Co3O4 nanostructures was investigated. Best concentration of NH3 for degradation of methyl orange and rhodamine B is 3 mol, and most appropriate precursor of cobalt for the demolition of dyes is Co(Hsal)2. Photo-degradation of Rhodamine B and methyl orange (89%) was performed using Co3O4 nanoparticle (band gap 1.7 eV) synthesized by Co(Hsal)2 as precursor of cobalt under visible light irradiation for 4h.