Reduced graphene oxide/ZnFe2O4 nanocomposite as an efficient catalyst for the photocatalytic degradation of methylene blue dye

Abstract

This research effort reports the design and development of reduced graphene oxide/zinc ferrite (rGO/ZnFe2O4) nanocomposites for the photo-oxidative degradation of methylene blue (MB) dye. The composite formation of rGO sheets with ZnFe2O4 nanostructures was achieved by a simple process of one- step solvothermal strategy, in which the simultaneous reduction of GO and Zn2+ and Fe3+ ions was achieved. The morphological studies revealed that the surfaces of rGO sheets were densely covered by the 280-nm-sized spherical ZnFe2O4 nanostructures and the average size of nanoparticles that constitutes the sphere was found to be 10 nm. The cubic spinel structure of prepared ZnFe2O4 nanomaterials was confirmed from the diffraction patterns and the nucleation sites exploited for the composite formation of ZnFe2O4 nanostructures with rGO sheets was explored by using FT-IR spectroscopy. The catalytic efficiency of prepared nanostructures toward MB dye degradation in the presence of H2O2 was evaluated in detail, in which rGO/ZnFe2O4 composite exhibited the remarkable catalytic activity toward MB degradation. The complete MB degradation observed at rGO/ZnFe2O4 composite is attributed to the π–π interaction, hydrogen bonding and electrostatic interaction exerted between the rGO/ZnFe2O4 and MB dye and the involved degradation reaction followed a pseudo-first-order kinetics. Thus, the proposed effort has not only provided a simple approach to synthesize the ZnFe2O4-based composites but has also provided a feasible solution for the effective and economically viable approach for the complete degradation of hazardous organic dye.