Preparation Of Silver Oxide-based Composites Photocatalytic And Their Photocatalytic Performance For Pollutants

In recent years,photocatalytic technology provided us with a clean and efficient way to solve global environmental pollution problems.Ag₂O is a p-type narrow-bandgap semiconductor material,which has attracted much attention due to its excellent optical and electrical properties.However,due to its photocorrosion at room temperature and the high recombination rate of electrons and holes,it is greatly restricted in photocatalytic applications.In order to make up for the shortcomings of Ag₂O photocatalysts in practical applications,this article uses two methods of semiconductor composite and carrier surface immobilization to prepare g-C₃N₄/Ag₂O and Ag₂O/FACs composite photocatalysts respectively,and catalytically degrade organics under near infrared.The performance and reaction mechanism of pollutants were studied.The following conclusions are drawn:?1?The g-C₃N₄/Ag₂O composite photocatalyst was prepared by a simple chemical synthesis method.In the composite sample,the lattice fringes between Ag₂O and g-C₃N₄ overlap to form a p-n heterojunction structure.Under near infrared light,the photocatalytic efficiency of g-C₃N₄/Ag₂O with a mass ratio of 1:16 to rhodamine B?RhB?reached 61.40%,which was higher than 46.21%of Ag₂O.Chemical fluorescence and free radical capture experiments show that under near infrared light,h⁺and·O₂?work together to oxidize and decompose RhB molecules.Through energy band structure analysis,the matching energy band structure between Ag₂O and g-C₃N₄ is conducive to the construction of p-n heterostructure,which promotes the separation and migration of photogenerated carriers and enhances the photocatalytic activity of the composite photocatalyst.?2?Through acidification etching modification,the adsorption performance of fly ash floating beads?FACs?is increased to 58.40%.A series of Ag₂O/FACs composite photocatalysts were prepared by simple chemical synthesis.Under near-infrared light,the Ag₂O/FACs composite photocatalyst with the best compounding ratio of 3:1 has a degradation rate of 97.50%for MB.Among them,h⁺oxidizes MB molecules in the reaction system.In the stability study,the photocatalytic efficiency is still 86.40%after four cycles of experiments.As a carrier of Ag₂O,FACs can effectively increase its effective surface area and active sites,and improve the adsorption performance and recovery utilization rate of the composite photocatalyst.