Preparation Of MOFs/GO Composite Materials And Study On Tructure Properties

Metal-organic framework materials(MOFs)are a new class of functional inorganic-organic hybrid materials,which have developed rapidly.Because of its high surface area,adjustable pore size and structure,the surface is easily modified and functionalized.This paper is based on two iron-based MOFs materials MIL-101(Fe)and MIL-53(Fe),successfully doped GO/MIL-101(Fe)to MIL-101(Fe)doped Graphene Oxide(GO),MIL-53(Fe)doped with Co2+to form bimetallic MOFs.Using XRD,FT-IR,SEM,BET and other tests to characterize and analyze the sample,and test its adsorption and photocatalysis of simulated wastewater.The main research results are as follows:(1)MIL-101(Fe)material has been successfully prepared,has good quality,has an octahedral morphology,and its crystal structure has integrity.The successfully composited GO/MIL-101(Fe)composite material,MIL-101(Fe)grows uniformly on the surface of GO and can basically maintain its crystal structure,but the regularity and integrity of crystallinity and crystal morphology are slightly reduced.MIL-53(Fe)material was successfully prepared with complete crystal form and high quality.Compared with MIL-101(Fe),MIL-53(Fe)has a smaller specific surface area,and MIL-53(Fe)and MIL-The 53(Fe,Co)materials all showed polyhedral pyramid-shaped pyramidal crystals,indicating that MIL-53(Fe,Co)still retained the structure of MIL-53(Fe),and the specific surface area increased.(2)Adsorption experiments of MIL-101(Fe)and GO/MIL-101(Fe)materials on methyl orange and Cr6+simulation liquid show that GO/MIL-101(Fe)composite materials doped with GO in different proportions The adsorption effect of methyl orange and Cr6+simulated liquid is higher than that of single MIL-101(Fe),and the best adsorption effect is 10%GO/MIL-101(Fe)composite.The adsorption amount of methyl orange is from 117.74 mg/g increased to 186.20 mg/g,and the adsorption amount of Cr6+increased from 12.42 mg/g to 25.24 mg/g.The adsorption effect of MIL-101(Fe)and GO/MIL-101(Fe)materials on methyl orange and Cr6+simulation solution increased with time,and the adsorption equilibrium time was 180 min.The adsorption behavior of the adsorbent on methyl orange and Cr6+simulated liquid is more in line with the Langmuir adsorption isotherm equation,and the adsorption kinetics are more in line with the second-order kinetic model.Spontaneous endothermic reaction process.The material has good recyclability and can be recycled at least 3 times.(3)The photocatalytic performance of MIL-101(Fe)and GO/MIL-101(Fe)materials on methyl orange simulation liquid was preliminary investigated.Experiments show that the photocatalytic effect of GO/MIL-101(Fe)composites doped with GO in different proportions on methyl orange simulation liquid is higher than that of single MIL-101(Fe),and the best photocatalytic effect is 10 The removal rate of 10%GO/MIL-101(Fe)composites from methyl orange increased from 64%to 82%.The reaction tended to be stable when the reaction time was 180 min.The photocatalytic behavior of the material on methyl orange is more in line with the photocatalytic first-order reaction kinetics,and the material has better recycling efficiency,which can be used at least 4 times.(4)MIL-53(Fe)and MIL-53(Fe,Co)materials' adsorption experiments on Congo red simulation liquid show that:MIL-53(Fe,Co)bimetal materials doped with different proportions of Co2+have no effect on Congo red simulation liquid.The adsorption effect is higher than that of single MIL-53(Fe),and the best adsorption effect is MIL-53(Fe,Co)when the ratio of iron to cobalt is 3:2,and the adsorption amount of Congo red is from 85.16mg/g When it increased to 113.3mg/g,the adsorption effect on Congo red increased with time,and the adsorption equilibrium time was 180min.The adsorption behavior of Congo red by the adsorbent material conforms to the Langmuir adsorption isotherm equation,the adsorption kinetics conforms to the second-order kinetic model,and the adsorption of methyl orange is a spontaneous endothermic reaction process.The adsorbent has good recyclability and can be reused at least 4 times.