Photocatalytic degradation of methylene blue from aqueous solution using Fe3O4@SiO2@CeO2 core-shell magnetic nanostructure as an effective catalyst

Abstract

In the present study, the core-shell magnetic nanostructure of Fe₃O₄@SiO₂@CeO₂ was synthesized to investigate its use as an effective photocatalyst for methylene blue removal. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and a vibrating sample magnetometer (VSM). The photocatalytic activity for the Fe₃O₄@SiO₂@CeO₂ core-shell magnetic nanostructure was investigated under visible light by determining the degradation rate of methylene blue for 50 min. At the end of the photocatalytic degradation process, the magnetic catalyst was recovered by an external magnetic field. The performance of the proposed catalyst for the degradation of methylene blue was improved with the optimization of the effective parameters such as the amount of catalyst, pH, and reaction time. Under optimum conditions, the efficiency of methylene blue removal with the proposed photocatalyst remains higher than 92 % after five times of use. The second pseudo-model was selected as the kinetic model to calculate catalytic degradation. The present results show that the Fe₃O₄@SiO₂@CeO₂ can be an efficient nanocatalyst for the photodegradation of dye pollutants.