Preparation And Visible-light Catalytic Performance Study Of Multiple Complex Based On Graphitic Carbon Nitride

Graphitic nitride carbon?g-CN?has a promising prospect and has been the focus of research on photocatalysis in recent ten years.In this paper,visible-light-driven polymer-porous graphite carbon nitride?pg-CN?was synthesized through simple and environmentally friendly thermal polymerization method with dicyandiamide/melamine as precursors and protection of high temperature thermal polymerization with melamine as precursors,silica nanospheres/SBA-15 as template,using,At the same time,by potassium doping,coupling with carbon quantum dots,cadmium sulfide quantum dots,binary or ternary graphite carbon nitride compounds were prepared.The catalysts were characterized and photocatalytic performance was evaluated through degradation of organic pollutants.The specific research contents are as follows:?1?Porous graphitic carbon nitride containing potassium?K⁺/pCN?was prepared with cheap and environmentally friendly materials and was applied to degrade typical organic pollutants?2,4-DCP?.Using Fourier transform infrared spectroscopy?FT IR?,X-ray diffraction?XRD?,transmission electron microscope?TEM?,scanning electron microscope?SEM?,N₂ adsorption desorption technology,photoluminescence?PL?spectra,photocurrent?PC?test and ultraviolet-visible diffuse reflection spectrum?DRS?for regular mechanism analysis and exploration,for the preparation of catalysts have been characterized.Because of its smaller surface area,narrower band gap and more structural defects,the visible photocatalytic degradation of 2,4-DCP is significantly enhanced.?2?A one-step synthesis method was used as the template agent for SBA-15,and melamine was the precursor,and CQD,pg-CN was prepared under 550?,and the deposition amount of carbon quantum dot was adjusted by regulating the volatilization and drying time of ethylene glycol.XRD,FT-IR,DSR and other methods were used to characterize the catalysis and the experimental results showed that CQD@pg-CN had higher photocatalytic activity than pg-CN.?3?Through several simple and feasible steps,a series of porous carbon nitride?pg-cn?modified by different amounts of carbon quantum dots?CQD?and cadmium sulfide quantum dots?CDDS?were synthesized.In visible light,the reaction rate of the optimal catalyst was more than 6 times faster than that of the pure pg-CN,and3.1 times faster than the pure cadmium sulfide.Through TEM&HRTEM,carbon point and cadmium sulfide quantum dots can be observed on the carbon nitride hole wall.The physical and chemical properties of the selected samples were characterized by XRD,FT-IR,X-ray photoelectron spectroscopy?XPS?,BET,DRS,PL,PC and other methods.The possible mechanism of enhanced visible photocatalytic activity was studied.The high specific surface area of the turnary composite material,the good visible light acquisition ability of CdS and the good electronic storage capacity of CQD have promoted the final catalytic effect.