Synthesis of Chromium Doped Cobalt Oxide (Cr:Co 3 O 4 ) Nanoparticles by Co-Precipitation Method and Enhanced Photocatalytic Properties in the Visible Region

In the present work, Co3O4, 1% chromium doped Co3O4 (1% Cr:Co3O4), and 5% chromium doped Co3O4 (5% Cr:Co3O4) was successfully prepared by simple chemical co-precipitation method followed by calcination at 400°C for 3 h. The synthesized nanoparticles materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), Brunauer Emmett Teller analysis (BET), and UV-visible spectroscopy. XRD confirmed the formation of cubic nature of nanoparticles while SEM images shown spherical structure. BET analysis confirmed the mesoporous behaviour of nanoparticles. UV-Visible spectra have been used to determine band gap and photo-oxidation behaviour of organic dye methyl orange. Experimental data suggested that 5% Cr:Co3O4 nanoparticles catalyst possessed the highest catalytic activity towards MB degradation in aqueous solution at the tested concentration level of 50 mg/L, higher than that of pure Co3O4.