In‐Situ Construction of P‐Doped G‐C ₃ N ₄ /Ag ₃ PO ₄ Z‐Scheme Heterojunctions with Broad pH Adaptability in Combination with Persulfate for Ultra‐Efficient Photocatalytic Degradation of RhB

Abstract It is of vital importance to develop highly efficient photocatalysts capable of removing dyes from actual wastewater environments. In this study, we constructed a in‐situ, novel P‐doped g‐C 3 N 4 /Ag 3 PO 4 Z‐scheme heterojunction photocatalyst (AgPCN) to degrade rhodamine B(RhB) in wastewater activated by persulfate (APS). Without the addition of persulfate, the kinetic degradation constant of RhB degraded by AgPCN can reach 0.53619 min −1 . Under the activation with a specific amount of persulfate, the kinetic degradation constant of RhB in the AgPCN + APS photocatalytic system can reach 0.78844 min −1 , which is 1.47 times higher than that of pure AgPCN. This is attributed to the structural defects of AgPCN itself and the energy level transformation caused by doping. Additionally, the activation of APS stimulates the generation of free radicals such as SO 4 · 2− , O 2 · − , and ·OH during the degradation process of AgPCN. It is worth noting that the AgPCN + APS system has a wide pH tolerance, indicating its application potential in complex actual wastewater environments. After three cycles of experiments, it still maintained a degradation efficiency of over 95%. Therefore, the AgPCN + APS system features excellent stability and wide applicability, providing a promising technical approach for the industrial treatment of dye wastewater.