Construction And Photocatalytic Performance Of Conjugated Porous Polycarbazole Composite

Conjugated porous polycarbazole has a rigid conjugated structure and a three-dimensional network structure,large specific surface area,good thermal and chemical stability,and excellent photoelectric performance.It has broad application prospects in the fields of gas adsorption,sensing,catalysis,etc.Carbazole（Cz）and p-fluorobenzaldehyde were used as raw materials to prepare an aldehyde functionalized carbazole monomer（Cz-F）through N-arylation reaction.When the reaction temperature is 130℃and the reaction time is 24 h,the yield is the highest.Conjugated porous polycarbazole（PCz-F）was prepared by oxidative coupling method and Friedel-Crafts alkylation reaction using carbazole functionalized with aldehyde group as monomers.When the ratio of Cz-F to Fe Cl₃is 1:15,the reaction time is 24 h,and the yield is the highest.Its chemical composition and external morphology were characterized by Fourier Infrared Spectroscopy（FT-IR）,Scanning Electron Microscope（SEM）,Transmission Electron Microscope（TEM）,Specific Surface Area Test（BET）.Ag/PCz-F composite materials were prepared by dipping method using PCz-F and silver nitrate as raw materials.The visible light catalytic activity of Ag/PCz-F composite material was studied by catalytic reduction experiment of p-nitrophenol（4-NP）under visible light.The results show that a small amount of Ag adsorbed on the surface of PCz-F can significantly improve the separation effect of photogenerated electron-hole pairs.When the mass ratio of Ag to PCz-F is 1:100,the photocatalytic activity is highest.In order to improve the photocatalytic performance of hydrophobic Ag/PCz-F composite material,the Ag/PCz-F/Si O₂composite material was prepared with Si O₂as the carrier,and the dispersion in the solution was enhanced to improve the photocatalytic activity.As the content of Si O₂increases,the photocatalytic activity first increases and then decreases.When the mass ratio of PCz-F to Si O₂is 1:1,the photocatalytic activity exhibits the highest.The chemical composition,surface morphology and photoelectric properties of Ag/PCz/Si O₂composite materials were analyzed by XRD,SEM,TEM,Mapping,PT,EIS and other methods.