Application Of Covalent Organic Framework Materials (COF-LZU1) In Adsorption Of Metal Ions And Catalytic Reduction Reaction

Covalent Organic Framework Materials（COFs）have the advantages of orderly structure,adjustable pore size,large specific surface area and so on.As an Organic crystal porous materials,they are also called"Organic molecular sieve"because of their similar properties to molecular sieve.It can design different functional monomers to synthesize different materials with high adsorption performance and catalytic performance.The imine covalent organic framework material is generated by dehydration reaction of aldehydes and amines,and the imine bond is conducive to the adsorption of metal ions,and the covalent organic framework material after the adsorption of metal ions shows good catalytic activity and stability.This study will mainly carry out the following work:1.Study the synthesis technology of covalent organic framework material（COF-LZU1）,including the synthesis of monomer homophentriformaldehyde and optimization of the reaction conditions of COF-LZU1;2.The adsorption performance of COF-LZU1 for metal ions was studied,with emphasis on the adsorption law of COF-LZU1 for gold and silver ions in groupⅠB elements;3.The catalytic performance of metal@COF-LZU1 composite was studied.The catalytic reduction of4-nitrophenol with Au³⁺@COF-LZU1 was investigated.Covalent organic framework material COF-LZU1 was synthesized by reaction reactor thermal solvent synthesis using homophentriformaldehyde and 1,4-p-phenylenediamine as functional monomers.Solid catalysts Au³⁺@COF-LZU1 and Ag⁺@COF-LZU1 were obtained by intermittent adsorption method and used for the catalytic reduction of 4-nitrophenol.The structure,morphology,adsorption performance and catalytic performance of the materials were analyzed by XRD,SEM,FT-IR,atomic absorption spectrometer and UV spectrometer.The results show that COF-LZU1 has good adsorption effect on both gold and silver ions.Solid catalysts Au³⁺@COF-LZU1 and Ag⁺@COF-LZU1 can effectively promote the conversion of4-nitrophenol to 4-aminophenol.Au³⁺@COF-LZU1 and Ag⁺@COF-LZU1 are activated after repeated use for 10 times and 3 times respectively.It reflects the good catalytic activity and high stability of the catalyst.