Synthesis And Fluorescent Property And Electrochemical Property Of Metal-Organic Frameworks

As a new highly ordered porous crystalline material,Metal-organic frameworks(MOFs)have high specific surface area,adjustable pore size and can be modified,show the potential value of the application in the field of gas adsorptionand separation,energy gas storage,fluorescent probes,electrocatalysis and so onIn this thesis,based on the design and synthesis of MOF materials and the selection of functional MOF materials,we aim to make MOF materials target-oriented and reasonably selected according to specific performance requirements.Using post－synthesis method,several kinds of fluorescent property and electrocatalytic materials were successfully synthesized by carefully selection reaction conditions.The structures and properties of the materials are characterized by X-ray single crystal diffraction,elemental analysis,thermogravimetric analysis,infrared analysis,X-ray powder diffraction,scanning electron microscopy,electrochemical tests etc.The main research contents are as follows(1)Using 4,4’,4",4"’-(pyrene-l,3,6,8-tetrayl)tetrabenzoic acid as organic ligands,three complexes 1-3 were synthesized by self-assembly with metal ions(Pb2+,Cd2+,Ca2+).XRD,TG,IR and solid statelluorescence were used to characterize the complex 1-3.Fluorescence measurements of complex 3 showed that complex 3 had moderate selectivity for metal cations Mn2+ andAl3+.(2)Selecting a good stability of the iron-based metal organic framework material PCN-250-Fe,Pt ions are adsorbed by its porosity.After low temperature reduction,the electrocatalytic hydrogen evolution performance was measured.The results show that in the case of low Pt content,the hydrogen evolution effect is very close to 20%Pt/C catalyst,which has practical significance.(3)We choose cheap and easy-to-use ZIF-67 and recycled wood chips as raw materials,and load the sawdust with ZIF-67.A one-step calcination method was used to carry out phosphating and carbonization at the same time to prepare a porous carbon material with metal phosphide adsorbed on the surface.And its oxygen reduction performance of the study found that the material has good oxygen reduction activity,stability and methanol resistance.