2-Aminoterephthalic Acid-MOFs Functional Composite Materials Construction And Its Photocatalytic Performance Study

With the accelerating development of global industrialization and urbanization,water pollution has become increasingly prominent.Effective controlling heavy metals and antibiotics has become more urgent.Compared with traditional methods,photocatalytic technology shows low energy consumption,high removal rate and less secondary pollution.It is considered to be one of the most promising wastewater purification strategy.While due to the low utilization rate of sunlight,it largely hampers its wide application.Aiming at this scientific issue,in this paper,based on metal-organic frameworks（MOFs）material with large specific surface area and easily regulating,we synthesized Ag/NH₂-MIL-125（Ti）,Ag/Ag Cl/NH₂-MIL-88B（Fe）,NH₂-MIL-88B(Fe_x In_1-x)and NH₂-MIL-68(In_x Fe_1-x)catalysts.With Cr（VI）and tetracycline hydrochloride（TC-HCl）as the target pollutants,the photocatalytic performance of the as-prepared catalysts were investigated,and the reactive oxygen species in the catalytic reaction processes were discussed.The photo-generated charge migration and photocatalytic reaction mechanism were also proposed.The main findings are as follows:（1）"Sesame cake"Ag/NH₂-MIL-125（Ti）catalyst was prepared by solvothermal-UV reduction route.Due to the uniform loading of Ag nanoparticles,it could broaden the visible light response range and improve the visible light catalytic performance.Under visible light conditions,the photocatalytic reduction rate of Cr（VI）reached to 57.04%,which was 2.74times than that of NH₂-MIL-125（Ti）,which was ascribed to this special morphology and the heterostructure formation between Ag and NH₂-MIL-125（Ti）.（2）Ag/Ag Cl/NH₂-MIL-88B（Fe）composite photocatalytic material was prepared by the solvothermal-ultraviolet reduction method.Due to the surface ion resonance effect of Ag,the energy band structure of this catalyst was optimized,and the visible light response performance was improved.Under visible light conditions,the photocatalytic reduction efficiency of Ag/Ag Cl/NH₂-MIL-88B（Fe）（10 wt%）photocatalytic reduction of Cr（VI）was81.78%,which was 2.26 times than that of NH₂-MIL-88B（Fe）.（3）In（Ⅲ）-doped NH₂-MIL-88B(Fe_x In_1-x)was prepared by one-pot reaction.The introduction of In（Ⅲ）could optimize its energy band structure,also enhance its visible light absorption ability.Under visible light reaction conditions,the photocatalytic reduction efficiency of Cr（VI）by NH₂-MIL-88B(Fe_0.6In_0.4)was increased to 98.16%,and the catalytic degradation efficiency of TC-HCl was 65.90%,which was 1.94 and 2.14 times than those of NH₂-MIL-88B（Fe）,respectively.The reactive oxygen species generation during the reaction were verified by ESR.（4）Fe（Ⅲ）-doped NH₂-MIL-68(In_xFe_1-x)was constructed by one-pot reaction.Based on the synergistic effect of In-Fe bimetal,the rate of electron-hole recombination was reduced and its photocatalytic performance was improved.Under visible light reaction conditions,the photocatalytic reduction efficiency of Cr（VI）by NH₂-MIL-68(In_0.4Fe_0.6)was 99.09%,and photocatalytic degradation efficiency of TC-HCl was 62.13%,which was 5.00 and 2.56 times than those of NH₂-MIL-68（In）,respectively.