Preparation and characterization of AgVO3/Ag4V2O7/BiOI double S-scheme heterojunctions for the photocatalytic degradation of methylene orange and tetracycline

A novel visible-light-driven AgVO3/Ag4V2O7/BiOI (AVO/AVO7/BOI) double S-scheme heterojunction photocatalyst was prepared by loading rod-like AgVO3 and BiOI plates onto irregular hexagons of Ag4V2O7. The morphologies, optical properties, and energy band structures of the prepared photocatalysts were studied using a series of characterization methods. When the mass ratio of BOI is 45%, the photocatalytic performance of AVO/AVO7/BOI is the best, and it can completely remove methylene orange and tetracycline within 80 minutes with excellent recyclability. The enhanced photoactivity could be due to the irregular hexagonal morphology and composition of the terpolymer heterojunction, which provide more active sites and promote the separation of photogenerated carriers. Finally, density functional theory calculations further confirmed the mechanism of photocatalytic degradation. This study provides a facile strategy for the design and synthesis of silver vanadate-based photocatalysts to photodegrade organic pollutants in water.