In situ loading of Ag2WO4 on ultrathin g-C3N4 nanosheets with highly enhanced photocatalytic performance

Ultrathin g-C3N4 nanosheets (g-C3N4NS) with improved electron transport ability and large number of active sites are employed instead of bulk g-C3N4 to prepare the Ag2WO4/g-C3N4NS heterostructured photocatalysts, which exhibit remarkable photocatalytic activity for wastewater treatment. [Display omitted] •Ag2WO4/g-C3N4-NS photocatalysts were obtained by a deposition-precipitation method.•Ag2WO4/g-C3N4-NS possess large surface areas and increased lifetime of charges.•Ag2WO4/g-C3N4-NS exhibit enhanced activity on degradation of RhB and MO.•The photocatalytic mechanism of the Ag2WO4/g-C3N4-NS system were investigated. The g-C3N4 nanosheets (g-C3N4NS) exhibit more excellent property than common bulk g-C3N4 (g-C3N4-B) due to their large surface areas, improved electron transport ability and well dispersion in water. In this work, ultrathin g-C3N4NS with a thickness of about 2.7nm have been synthesized by a simple thermal exfoliation of bulk g-C3N4, and then Ag2WO4 nanoparticles are in situ loaded on their surface to construct the Ag2WO4/g-C3N4NS heterostructured photocatalysts. Due to their unique physicochemical properties, the as-prepared heterostructures possess a fast interfacial charge transfer and increased lifetime of photo-excited charge carriers, and exhibit much higher photocatalytic activity. Under visible light irradiation, the optimum photocatalytic activity of Ag2WO4/g-C3N4NS composites is almost 53.6 and 26.5 times higher than that of pure g-C3N4-B and Ag2WO4/g-C3N4-B heterostructures towards the degradation of rhodamine B, respectively, and is almost 30.6 and 9.8 times higher towards the degradation of methyl orange, respectively. In addition, the natural sunlight photocatalytic activities of the as-prepared samples are also investigated.