Formation of Ag 3 PO 4 /AgBr composites with Z-scheme configuration by an in situ strategy and their superior photocatalytic activity with excellent anti-photocorrosion performance

A novel Ag 3 PO 4 /AgBr composite with Z-Scheme structure was constructed and synthesized via a simple in situ ion-exchange strategy on the surface of Ag 3 PO 4 tetrahedra in an alkaline environment. The as-prepared Ag 3 PO 4 /AgBr composite has an intimate contact interface and exhibited enhanced visible-light photocatalytic activity, accompanied by superior stability toward degradation of methylene blue (MB) in aqueous solution. Also, a variety of pollutants can be degraded without selectivity, and the degradation efficiency was over 96%. Changes in the bandgap and the detailed degradation mechanism of the Ag 3 PO 4 /AgBr composite were analyzed and revealed using characterization analysis, theoretical calculations, and further designed experiments. Sufficient interfacial contact between Ag 3 PO 4 and AgBr was favorable for transferring carriers and lengthening the lifetime of the Z-Scheme system, which simultaneously inhibit photocorrosion and maintain a high degradation rate. The trapping experiments indicate that h + is a dominant reactive species for the degradation of MB. This Ag 3 PO 4 /AgBr photocatalyst with Z-Scheme structure shows great potential for replication and large scale impact on the environmental purification of organic pollutants.