Silver chromate modified sulfur doped graphitic carbon nitride microrod composites with enhanced visible-light photoactivity towards organic pollutants degradation

摘要

The elimination of pollutants from wastewater using visible-light-driven photocatalysts has been attracted more and more attentions due to their higher sunlight utilization compared to conventional ultraviolet photocatalysts. Sulfur doped g-C3N4 microrods (SCN) modified with silver chromate (Ag2CrO4) were prepared by precipitation method. Several characterization methods, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra and UV-Vis diffuse reflectance spectra (UV-Vis DRS), were applied to study the morphologies and phase structures and optical properties of as-synthesized semiconductor photocatalysts. Novelty Ag2CrO4/SCN heterostructures exhibited enhanced photodegradation of methyl orange under visible light irradiation. Finest photocatalytic activity of 30%-Ag2CrO4/SCN for the degradation of MO was 5.5 and 13.5 times higher than that of single Ag2CrO4 and SCN, respectively. The design of a Z-scheme system in Ag2CrO4/SCN heterostructures promoted the photocatalytic performance through enhancing redox ability, facilitating the light absorption and promoting the charge separation.