Design and Application of Ag3PO4@Ag4V2O7 Z-Scheme Photocatalysts with a Micro-Nano Tube-Cluster Structure for the Co-Degradation of Nitrate and Ammonia in Wastewater

Water eutrophication due to the discharge of nitrogen-containing wastewater has aroused widespread concern around the world, and photocatalysis is confirmed a promising method to dispose the problem. Nonetheless, co-degradation of ammonia nitrogen and nitrate nitrogen is still nerve-wracking. In this work, the Ag3PO4@Ag4V2O7 Z-scheme photocatalysts with a micro-nano tube-cluster structure were designed by a facile in situ growth method, which realized concurrent removal of nitrate and ammonia in wastewater, without the addition of hole scavengers or electron scavengers, due to its high redox ability. The experimental results demonstrated that P@V1 composites showed superior rate (2.79 times enhancement) and higher conversion (3.00 times enhancement) compared with the pure Ag4V2O7 crystals for ammonia degradation and the pure Ag3PO4 crystals for nitrate reduction, respectively. Therefore, Z-scheme photocatalysts offer a new thought for co-degradation of low concentrations of nitrogenous contaminated water.