Visible light photocatalytic activity of nanocrystalline CoxMg1-xFe2O4 (x = 0-1)

Abstract

The sol-gel combustion method was applied for synthesis of spinel magnesium cobalt ferrites CoxMg1-xFe2O4, with varying cobalt and magnesium content, x = 0.0, 0.1, 0.3, 0.5, 0.7, 0.9. Magnesium nitrate, cobalt nitrate and iron nitrate were used as oxidizers and citric acid was used as a reducing agent. Structural and morphological properties of the obtained ferrite powders were investigated and characterized by X-ray diffraction (XRD), Raman spectroscopy, Field emission scanning electron microscope (FESEM) and Fourier transform infrared (FT-IR) spectroscopy. Optical properties were investigated by UV-VIS spectrophotometry. A cubic spinel structure with multigrain agglomerates formed. Visible light photocatalytic activity of the spinel ferrite powder samples was evaluated by measuring the rate of photodegradation reaction of methylene blue (MB). After 240 min Co0.1Mg0.9Fe2O4 showed the best rate of photodecomposition of MB resulting in 90% of its initial concentration in an alkaline environment.