Electrochemical Synthesis Of IRMOF-3 For Detection Of TNP

Metal-Organic Frameworks(MOFs)materials are widely used in gas storage and separation,adsorption,catalysis,drug loading and fluorescence detection,owing to their porosity,high surface area,specific pore size and certain catalytic activities.The methods of synthesizing MOFs such as hydrothermal/solvothermal method,diffusion method and mechanical stirring method all have the disadvantages of high energy consumption,low yield,long time consuming and complicated operation.The electrochemical synthesis method has the advantages of mild conditions,simple operation,less time consumption,low energy consumption and without additional metal salts.However,electrochemistry is still in the state of beginning,and the synthesis of MOFs is limited.Therefore,it is still a challenge to extend the electrochemical synthesis of MOFs.In this paper,IRMOF-3 was synthesized for the first time by using electrochemical method with zinc plate as anode,copper plate as cathode,2-NH2-BDC as organic ligand,DMF and ethano mixed solution as solvent and TBAB as conductive salt.The structure and morphology of the obtained product were characterized by means of XRD and SEM.The synthesis conditions such as solvent volume ratio of DMF and ethanol,voltage and reaction time were optimized.The effects of different synthesis conditions on the structure and morphology of IRMOF-3 were also analyzed.When the ratio of DMF to ethanol is 20:30,the applied voltage is 6 V and the reaction time is 3 h,the obtained IRMOF-3 material had high crystallinity and uniform spherical morphology.The elemental composition and distribution,coordination mode and thermal stability of the synthesized materials under the optimized conditions were further characterized by EDS,EDS-Mapping,FT-IR and TG analysis.The results shows that the elements of synthesized IRMOF-3 are well-distributed and the thermally stable is satisfactory.Different concentrations of TNP in water were detected using IRMOF-3 synthesized under optimal conditions.Sensitivity testing,detection performance testing,anti-interference performance testing and stability testing were carried out in the testing process,and the detection mechanism was analyzed and explored.The results show that IRMOF-3 synthesized by electrochemical emits fluorescence with a wavelength of 460 nm under excitation at a wavelength of 340 nm.However,TNP in water can cause a certain degree of quenching of IRMOF-3 fluorescence.The synthesized IRMOF-3 has a sensitivity of 10 s for TNP detection in water and a detection limit of 0.1 ppm,and has good anti-interference performance and stability.The detection mechanism was determined based on the combined effect of electron transfer and fluorescence filter effect.At the same time,the electrochemical synthesis of IRMOF-3 and hydrothermal synthesis of IRMOF-3 in the yield and the detection limit of TNP in water were compared.The results show that the electrochemical synthesis of IRMOF-3 is about 9 times to the yield of hydrothermal method at the same time conditions.The IRMOF-3 synthesized by hydrothermal method has a lower detection limit of 5 ppm for TNP in water.In summary,the electrochemical method not only has a greater advantage in the synthesis conditions,but also has a good prospect in the detection performance.