Synthesis Of Ag₃PO₄-based Semiconductor Photocatalysts And Their Performance In Photocatalytic Degradation Of Pollutants

In recent years,Ag₃PO₄ with a narrow band gap（2.45 e V）has photocorrosion under visible light irradiation,which affects its stability.To improve the performance of Ag₃PO₄,a lot of silver-based materials have been developed,which have attracted much attention due to their rapid response to visible light and excellent photocatalytic activity.Therefore,we prepared three-dimensional flower-like spherical Ag₃PO₄/MoS₂ photocatalyst and dual Z-scheme Ag₃PO₄/MoS₂/g-C₃N₄ photocatalyst to improve the performance of Ag₃PO₄.In order to ensure that the MoS₂ has good morphology,crystallinity and excellent thermal stability,We prepared MoS₂ that was reacted at different temperatures（100℃,150℃,200℃,230℃）for 24hours.MoS₂（230℃,24 h）has the best morphology,crystallinity and thermal stability.Then,we prepared Ag₃PO₄/MoS₂（AM-X）photocatalyst by in-situ deposition of Ag₃PO₄ nanoparticles on the surface of MoS₂ with different contents（10 mg,20 mg,30 mg）.Where X represents the mass of MoS₂.The photocatalytic degradation efficiency of the optimal AM-20 sample for Methylene blue（MB）,Rhodamine B（Rh B）,tetracycline（TC）was about 1.37,1.39 and 1.78 times of that of Ag₃PO₄,respectively.There are two reasons for the improvement of AM-X photocatalytic activity:（1）The introduction of MoS₂ broadens the visible light absorption range of AM-X composites;（2）Inhibit the rapid recombination of photo-generated carriers.Finally,we prepared dual Z-scheme Ag₃PO₄/MoS₂/g-C₃N₄（AMN-X）photocatalysts.Where X represents the mass of g-C₃N₄（X=3 mg,5 mg,7 mg）.The photocatalytic degradation efficiency of the optimal AMN-5 sample for Methylene blue（MB）is about 3.98,1.85,1.17 times that of g-C₃N₄,Ag₃PO₄,Ag₃PO₄/MoS₂,respectively.The enhanced catalytic activity of AMN-X may be attributed to the unique charge transfer mechanism of the dual Z-scheme heterojunction formed between Ag₃PO₄,MoS₂ and g-C₃N₄,which accelerates the rapid separation of photogenerated electron-hole pairs.