UV-Assisted Fabrication of Reduced Graphene Oxide Doped SiO2@TiO2 Nanocomposites as Efficient Photocatalyst for Photodegradation of Rhodamine B

Abstract

The core-shell nanostructure materials have gained great interests because of its excellent photocatalytic properties and promising applications in several fields. In this work, we prepared the core-shell SiO₂@TiO₂ nanocomposites by the versatile kinetics-controlled coating method. The graphene oxide (GO) was further reduced over SiO₂@TiO₂ using UV-assisted photocatalytic reduction method. The physicochemical properties of the as-prepared SiO₂@TiO₂/RGO nanocomposites were characterized by SEM, XRD, BET, EDS, and FTIR. Results showed that, TiO₂ was mainly composed of anatase phase with high crystallinity. Their photocatalytic activities were examined by the degradation of Rhodamine B (RhB) under UV light irradiation. The presence of RGO obviously improved the adsorption ability and photodegradation performance of the composites to RhB. The degradation kinetics of RhB can be described by the pseudo-first-order model. The optimum mass ratio of SiO₂@TiO₂ to RGO in the composite was 1/0.05 and the rate constant was about 4 times greater than that of the SiO₂@TiO₂.