Enhanced visible light photocatalytic oxidative desulfurization by BiOBr-graphene composite

A series of BiOBr-graphene photocatalysts was synthesized using hydrothermal method, and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, ultraviolet-visible diffuse reflection spectroscopy (DRS) and photoluminescence (PL) emission spectroscopy. The photocatalysts were evaluated for photocatalytic oxidative desulfurization of model oil. The optimal temperature, graphene loading and the amount of hydrogen peroxide (H₂O₂) were investigated. The oxidation reactivity of the different sulfur compounds was found to be in the order of DBT>4, 6-DMDBT>BT. Moreover, the mechanism of photocatalytic oxidation of DBT by BiOBr-graphene was proposed based on the present experimental results.