Synthesis, characterization and photocatalytic activity of novel mixed metal oxides/reduced graphene oxide hybrid catalysts

Abstract

A novel series of ZnBi₂O₄/rGO hybrid catalysts were synthesized via co-precipitation method. The as-prepared catalysts were characterized by X-ray diffraction, Fourier transform infrared, UV-vis diffuse reflectance spectra, Field-emission scanning electron microscopy and Transmission electron microscopy techniques. The photocatalytic activities of ZnBi₂O₄/rGO catalysts were conducted using Indigo Carmine and the ZnBi₂O₄/rGO offered better degradation of pollutants as compared to pristine ZnBi₂O₄. Among them, ZnBi₂O₄/rGO (rGO = 2%) owned the best photocatalytic activity, which can degrade more than 91 % of Indigo Carmine (50 mg/L) after 75 min visible light irradiation. The enhancement of photocatalytic properties of ZnBi₂O₄/rGO indicates that the xistence of rGO may have facilitated photoinduced electrons to move from ZnBi₂O₄/rGO, to rGO, which effectively cause separation of the photoinduced electron-hole pairs in ZnBi₂O₄. The ZnBi₂O₄/rGO can be considered as a promising photocatalyst for dye waste water treatment.