Synthesis Of Stereoporous Ag/AgCl?HS??CdS/TiO₂ And Their Photocatalytic Properties

With the development of society,the energy crisis and environmental pollution have be-come two major challenges for humanity.In view of the current situation,photocatalytic technology can effectively use solar energy to hydrolyze hydrogen and degrade organic po l-lutants in water.It can effectively alleviate the current situation and application prospects.Ag/AgCl and TiO₂ have received a great deal of attention as semiconductor photocatalyst with excellent properties,but they have defects such as wide band gap,low stability,and small specific surface area,which play an important role in their photocatalytic performance.Therefore,special structures construction,surface modification or other methods have been studied to enhance photocatalytic activity and stability.Herein,the hollow three-dimensional structure was constructed to enhance the catalytic ability and stability of the catalyst by changing the preparation methods and surface modifica-tion of Ag/AgCl and TiO₂.The samples were tested and characterized by XRD,HRTEM,SEM,TEM,PL,UV-Vis DRS,BET,and photocurrent.RhB,MO,MB,OTC,and TC were chosen as target contaminants to evaluate the performance of the catalyst.The crystals,mor-phology,optical properties and photodegradation mechanism were studied and analyzed.The specific research contents and results are as follows:?1?Hollow-structured Ag/AgCl?HS?was synthesized by ordinary chemical precipitation and redox method compared with the traditional chemical precipitation-photoreduction method of Ag/AgCl.After a series of characterization tests,it can be found that the specific surface area of the hollow structure of Ag/AgCl?HS?is twice that of Ag/AgCl,the specific surface area has been significantly increased,and its optical properties have been significantly improved;We evaluated the photocatalytic activity and stability of the material under visible light irradiation.The results showed that hollow Ag/AgCl?HS?has a high removal rate of rhodamine B,methylene blue,methyl orange,oxytetracycline and tetracycline with better photocatalytic activity and stability.?2?3D porous CdS/TiO₂-400 photocatalyst was prepared by hydrolyzation–hydrothermal-calcination method and CdS/P25-400 catalyst used for comparative study was prepared with the same method.The difference between the two structures was studied to analyze the optical properties and catalytic activity of the morphology structure on the material.After characteri-zation test analysis,the specific surface area of CdS/TiO₂-400 is nearly 3 times that of CdS/P25-400.CdS QDs have been successfully loaded onto the surface of porous TiO₂,and the size effect of the material has been highlighted.After calcination,the catalytic activity and stability have been greatly improved,and the defects of CdS easy-to-corrosion have been ef-fectively avoided at the same time.The material optical analysis shows that the combination of two semiconductor materials can improve the separation efficiency of electron-hole pairs and improve its light absorption capacity and conversion rate.Under visible light irradiation,methyl orange,terramycin and tetracycline were selected as target pollutants for their activity and stability tests.The results showed that CdS/TiO₂-400 possessed good photocatalytic ac-tivity and stability.