| Metal-organic frameworks(MOFs),also known as porous coordination polymers,are a new class of nanoporous functional materials formed by self-assembly of inorganic metal ions or metal clusters with organic ligands.Due to its adjustable size,ultra-high specific surface area and large porosity,and the variety of suitable metal ions and organic ligands,the structure of MOFs is diverse,making it widely used in gas adsorption,storage,and separation,electrode materials,drug delivery,catalysis and other fields.The main content of this paper is to prepare functional materials based on MIL-53(Fe),and study their applications as an electrochemical sensors for detection and as electrocatalysts for water decomposition,as follows:1.Electrochemical sensors based on MIL-53(Fe)were prepared,and the electrochemical detection experiments were performed on the presence of tetracycline in water.Experimental results show that the electrochemical sensor can detect trace tetracycline in water bodies,and it can also be effectively used in actual water bodies(tap water,river water).Specifically,the performance of tetracycline was analyzed by differential pulse voltammetry(DPV),which showed a high tetracycline sensitivity detection performance within the concentration range of 0.0643 mol/L-0.769 mol/L and 0.769 mol/L-1.53 mol/L,with a detection limit of 0.0260 mol/L.The sensor has good reproducibility that 7 different glassy carbon electrodes for DPV detection showed a relative low standard deviation of 7.3%.MIL-53(Fe)/GCE was placed in room temperature for three weeks before using for testing again,and the value of Ip retained more than 96%of that of the fresh one,indicating the good stability.The sensor has the advantages of simple preparation,low cost and high sensitivity and has great potential in the practical application of trace tetracycline detection.2.Ni-doped NH2-MIL-53(Fe)electrocatalytic material was prepared by a simple one-step solvothermal method.The materials were characterized by SEM,TEM,XRD,FTIR,and XPS,and their catalysis was investigated by electrochemical impedance(EIS)experiments.performance.The performance of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)was tested in a 1.0 mol/L KOH solution.The performance of the NM-Fe1Ni3/NF electrocatalytic material prepared when the molar ratio of metal Fe and Ni was 1:3,The overpotentials to achieve a current density of10 m A·cm-2in OER and HER were 229 m V and 164 m V,respectively,and the Tafel slopes of OER and HER were 43 m V·dec-1and 104 m V·dec-1.From the value of the electric double layer capacitance(Cdl),it can be seen that NM-Fe1Ni3has a higher electrochemically active surface area(ECSA)and a faster electron transfer rate.The overall water decomposition performance of the NM-Fe1Ni3/NF electrocatalyst was also tested.NM-Fe1Ni3/NF//NM-Fe1Ni3/NF only needs 1.65 V voltage to reach?15 m A·cm-2and achieve overall water decomposition,Has good stability.3.Catalytic materials with different ratios of NH2-MIL-53(Fe)and Ag In S2were prepared by a one-step solvothermal method.The materials were characterized by SEM,XRD,FTIR and XPS,and their catalytic performance was studied by electrochemical impedance(EIS)experiments.The performance of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)was tested in a 1.0 mol/L KOH solution.The results showed that the NM-Fe/50A material had the best catalytic performance when Ag In S2was added at a concentration of 50 mg.The overpotentials to achieve a current density of 10 m A·cm-2in OER are 90 m V and 357 m V,respectively,and the Tafel slopes of OER and HER are 45 m V·dec-1and 96 m V·dec-1,respectively.From the value of the electric double layer capacitance(Cdl),it can be seen that NM-Fe/50A has a higher electrochemically active surface area(ECSA)and a faster electron transfer rate.NM-Fe/50A/NF//NM-Fe/50A/NF exhibits good stability in chronopotentials that run continuously for 24 hours when reaching 10m A·cm-2and 30 m A·cm-2. |
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