Design And Synthesis Of Several Ordered Mesoporous Photocatalytic Material For Degradation Of Pollutants

With the rapid development of society and economy,the problem of environmental pollution is becoming increasingly serious,especially,the large amount of residues of antibiotic substances in water bodies poses a very serious threat to aquatic ecosystems and human health,which has caused widespread concern.Compared with traditional methods,photocatalytic technology has great application prospects in air purification,medical hygiene,deodorization and deodorization,and organic wastewater treatment due to its advantages such as energy saving and environmental protection,mild reaction conditions,high efficiency,and simple operation.However,the key is to design and synthesize efficient photocatalytic materials.Ordered mesoporous materials with rich and adjustable pore size,large pore volume,high specific surface area,and various chemical compositions,was considered to be very promising photocatalytic materials.In this paper,a series of mesoporous ferric oxides,manganese-based metal oxides and graphite-phase carbon nitrides with high specific surface area and large-pore size were synthesized.The mesostructure parameters(pore size,specific surface area,pore volume,etc.)was explored,Effect on photocatalytic performance.A series of mesoporous silica KIT-6 molecular sieves with different pore sizes(5.7?10.1 nm)and different specific surface areas(589?801 m2 g-1)were synthesized by hydrothermal method in adjusting hydrothermal temperatures.A series of ordered mesoporous hematite materials were synthesized by nanocasting from a series of pore size mesoporous silica KIT-6,and iron nitrate as precursor.Changing the pore size,pore connectivity,and specific surface area of the template KIT-6,which adjust the pore size(3.9-12 nm)and specific surface area(104-153 m2 g-1)of the material.The photocatalytic performance test found that the improvement of photocatalytic performance,increasing in the mesoporous ?-Fe2O3 pore size and pecific surface area to help the diffusion and transmission of tetracycline molecules and provide more active sites for the catalytic reaction.Especially,?-Fe2O3-40 with a high specific surface area(153 m2 g-1)and a large-pore size(12 nm)shows very high selectivity and photocatalytic degradation ability(100%)for tetracycline molecules,Comparing to ?-Fe2O3-140 with a low surface area(104 m2 g-1)and small mesopores(3.9 nm).Similarly,using KIT-6 as a template and manganese nitrate,zinc nitrate,nickel nitrate as precursors,a series of manganates such as MnO2,ZnMn2O4,and CoMn2O4 with high specific surface area and ordered large-pore mesoporous were synthesized.The findings of mesoporous MnO2 catalytic performance test that the MnO2-40 with high specific surface area(200 m2 g-1)and large mesopores(12.8 nm)was ordinary low specific surface area(84 m2 g-1)and small pore(4.2 nm)MnO2-140 material is 1.38 times about catalytic performance,and the catalytic efficiency is 84%and 62%,respectively.In addition,a series of ordered mesoporous g-C3N4 were synthesized using KIT-6 as a template and a cyanamide aqueous solution as a precursor,which has high specific surface areas(145?308 m2 g-1)and large-pore mesoporous(3.5?11 nm).It also shows good photocatalytic activity in antibiotic degradation applications.