Facile synthesis of CuCr2O4/CeO2 nanocomposite: A new Fenton like catalyst with domestic LED light assisted improved photocatalytic activity for the degradation of RhB, MB and MO dyes

Abstract

Here, we report the findings on CuCr2O4/CeO2 (CCO/CeO2) nanocomposite as a new heterogeneous Fenton like catalyst for the degradation of rhodamine B (RhB), methylene blue (MB) and methyl orange (MO) under domestic LED light irradiation. An extensive characterization of the samples were performed using several physicochemical techniques. A careful monitoring of photo-activities reveals the best performance of 10%CCO/CeO2 showing complete degradation of 10 ppm RhB, MB and MO dyes within 15, 20 and 30 min, respectively, in presence of 4 mM of H2O2. The visible light absorption of CeO2 is enhanced by CCO. The radical trapping and coumarin fluorescence probe methods suggest the generation of OH in the catalytic pathways. A comprehensive analysis of OH generation in presence and in absence of LED irradiation is presented to underscore both the Fenton like reactions of the nanocomposite system. Importantly, the nanocomposite catalyst shows encouraging recycling behavior through an intermediate heat treatment. The Fenton like catalytic behavior of marginally active CeO2 is dramatically enhanced in presence of CCO in the nanocomposite due to larger creation of oxygen vacancy. Finally, a plausible explanation of this novel catalytic behavior based on band bending across the junction of the two semiconducting oxides has been presented.