Preparation method of graphite type carbon nitride photocatalytic material

Abstract

The invention discloses a preparation method of a graphite type carbon nitride photocatalytic material, belonging to the field of the material preparation and photocatalytic technology. The graphite type carbon nitride photocatalytic material takes dicyandiamide and barbituric acid as co-precursors, adopts lithium chloride and potassium chloride as heating mediums, and is prepared in protective atmosphere through directly burning. The prepared g-C3N4 has excellent visible light absorption ability and the laminated structure characteristics, and has the degradation efficiency up to 83.8% to rhodamine B within 90min under visible light. The preparation method is simple, the raw materials are easily available, the visible light catalytic efficiency is high, and the graphite type carbon nitride photocatalytic material has wide application prospect in the photocatalytic field.

Description

technical field [0001] The invention belongs to the field of visible light catalysis, and in particular relates to a preparation method of a graphite-type carbon nitride photocatalytic material and its application in catalytically degrading pollutants in water under visible light. Background technique [0002] The problem of environmental pollution has increasingly become a major concern in today's society. In recent years, g-C 3 N 4 As a new type of important organic photocatalytic material, it has attracted wide attention due to the fact that C 3 N 4 Special semiconductor structure (Eg≈2.7eV), good stability, layered structure and easy-to-obtain raw materials are considered to have the potential to catalyze the degradation of organic pollutants; however, a large number of studies have found that high electron-hole recombination rate , low utilization rate of visible light, low specific surface area, low electron transport efficiency and easy agglomeration morphology lim...

AI Technical Summary

Problems solved by technology

[0002] The problem of environmental pollution has increasingly become a major concern in today's society. In recent years, g-C 3 N 4 As a new type of important organic photocatalytic material, it has attracted wide attention due to the fact that C 3 N 4 Special semiconductor structure (Eg≈2.7eV), good stability, layered structure and easy-to-obtain raw materials are considered to have the potential to catalyze the degradation of organic pollutants; however, a large number of studies have found that high electron-hole recombination rate , low utilization rate of visible light, low specific surface area, low electron transport efficiency and easy agglomeration morphology limit its application in the field of photocatalysis

[0003] Copolymerization of dicyandiamide and barbituric acid, the obtained product has excellent visible light absorption ability, but this experiment only uses a simple heating method, which makes the product appear serious agglomeration phenomenon, which reduces the separation efficiency of photogenerated electron-hole pairs , and excessive barbituric acid will also destroy the semiconductor characteristics; although high temperature calcination is beneficial to improve the crystallinity of the product and improve the separation efficiency of photogenerated electron-hole pairs, but too high temperature is not conducive to the stability of the product, so adopt A suitable heating temperature and heating method is to prepare layered C 3 N 4 In addition, using metal chloride or bromide as the heating medium to calcinate dicyandiamide can obtain carbon-nitrogen polymers with high crystallinity and obvious layered characteristics. 3 N 4 The structural unit is a triazine structure, which is not conducive to its efficient use of visible light; more importantly, the complicated experimental process and harsh conditions in the experiment also make it difficult to transform the experiment into a real production technology

Images