Photocatalytic effect of (TiO2/CeO2) with support of β-cyclodextrin for enhanced performance under solar light

Abstract

In this study, we have reported the interaction of binary metal oxides (TiO2/CeO2) with β-CD towards enhancement in the photocatalytic performance under solar light irradiation. The interactions of (TiO2/CeO2) with β-CD characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–Vis diffuse reflectance spectroscopy (DRS). XRD analysis shows that the fluorite structure of CeO2 and anatase structure of TiO2 have not been changed after the addition of β-CD. The structure morphology of (TiO2/CeO2), not changed by the addition of β-CD, is also confirmed by SEM analysis. Addition of CeO2 and β-CD with TiO2 is found to be significantly extended the absorption edge towards the visible region which is confirmed by UV-DRS spectral data. The photocatalytic activity of the modified (TiO2/CeO2)-β-CD system was evaluated by decolorization of Rhodamine B (RhB) dye taken as a model pollutant under solar light irradiation. The formation of an inclusion complex of RhB with β-CD is confirmed by UV–Vis analysis. Various experimental parameters like (TiO2:CeO2) ratio, initial concentration of RhB dye, dose of the catalyst, irradiation time and pH have been investigated. Kinetic results show that decolorization reaction follows pseudo-first-order kinetics. The mineralization of RhB dye was also confirmed by COD measurements. The modified (TiO2/CeO2)-β-CD system exhibits higher photocatalytic activity than (TiO2/CeO2), TiO2 and CeO2. A suitable reaction mechanism for the effective decolorization of RhB dye by (TiO2/CeO2)-β-CD system has also been proposed.