| Mesoporous SiO2 is a kind of mesoporous materials which is non-toxic,tasteless and no pollution,because of its small particle size,large surface area,the surface of the strong adsorption capacity,high chemical purity,good dispersibility and other specific properties,which has superior stability,reinforcing,thickening and thixotropy,plays a very important role in many disciplines and fields,especially as a catalyst carrier can effectively improve the catalytic performance of the catalyst.In this paper,mesoporous SiO2 powders were prepared by means of ultrasonic assisted and parallel flow mixing method,and their properties were characterized by XRD,TG,SEM,TEM,BET and so on.Because of its catalytic performance of nano TiO2 has good weatherability,chemical resistance,high,favored in the sewage treatment process.However,it is easy to agglomerate and agglomerate in the catalytic process,which results in the decrease of catalytic performance.Mesoporous silica?SiO2?is a kind of material with large specific surface area and internal channel,which can greatly enhance the catalytic efficiency of TiO2 photocatalyst on the surface of mesoporous silica.In this paper,mechanical grinding method,liquid phase precipitation method and solution blending method of SiO2/TiO2 composite powder was prepared,using XRD and TEM methods were characterized and tested on the photocatalytic degradation of reactive red dye effect,.The band gap of nano Cu2 O is 2.17 eV,which can complete a series of Catalysis under visible light,and it has a better application prospect compared with the nano TiO2 which can only be catalyzed by ultraviolet light.However,there are some defects in the nano Cu2 O itself,when the mesoporous silica?SiO2?is loaded with nano Cu2 O,its performance has been greatly improved.In this paper,the SiO2/Cu2 O composite powders were prepared by solution blending method,and characterized by XRD and TEM.The photocatalytic degradation of reactive red dye was tested.This paper is divided into five chapters:In the first chapter,the research status and important applications of mesoporous SiO2 are summarized.The research status of mesoporous SiO2/TiO2 and SiO2/Cu2 O composite powders is briefly explained.The purpose,content and significance of this research are discussed.In the second chapter,the mesoporous SiO2 was prepared by the ultrasonic assisted method under the acidic condition,and the BET was characterized by XRD,TG,SEM,TEM,and so on.The effects of aging time and aging pH value on the specific surface area,pore volume and pore size of mesoporous SiO2 were investigated.The third chapter respectively by mechanical grinding method,liquid phase precipitation method and solution blending method of SiO2/TiO2 composite powder was prepared.The XRD and TEM characterization,were tested for photocatalytic degradation of composite materials on the activity of red dye.Finally,it is concluded that the SiO2/TiO2 composite powder prepared by solution blending method has the best photocatalytic activity,and the degradation rate is 95%.In the fourth chapter,SiO2/Cu2 O composite powders were prepared by solution blending method.The XRD and TEM were used to characterize the photocatalytic degradation of reactive red dye.It was concluded that the photocatalytic properties of SiO2/Cu2 O composite powders prepared by solution blending method were better than those of SiO2/TiO2 composites,and the degradation rate of red dye was 99%.The fifth chapter summarizes the work done. |
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