| G-C3N4 as a non-metallic polymer semiconductor catalyst,since its first discovery in 2009 has excellent photocatalytic hydrogen production performance has been widely concerned.g-C3N4 has the lamellar structure of graphite,but the bulk g-C3N4 prepared by high temperature polycondensation has the problems of easy agglomeration,small surface area,low utilization rate of visible light and easy recombination of photogenerated carriers.Which are seriously restricting its application in the field of photocatalytic environmental management,organic synthesis and other fields.Aiming at these problems,a stripping method of g-C3N4 material was proposed,and the peeling effect of bulk solvent on bulk g-C3N4 was studied.The g-C3N4/Bi2WO6,g-C3N4/Bi2S3 composites were used to characterize the phase,morphology and optical properties of the composites by a series of characterization techniques.The photocatalytic degradation of organic dyes rhodamine B was studied.The main research contents are as follows:1.The effect of calcination temperature on the yield of g-C3N4 was studied by using bulk g-C3N4 by high temperature roasting of urea.The bulk g-C3N4 was then stripped by magnetic stirring at the respective micro-boiling temperatures using deionized water,anhydrous ethanol,isopropanol,tetrahydrofuran,dimethylformamide and acetone.The effects of different solvents on the stripping and photocatalytic properties of g-C3N4 were studied,and the possible peeling mechanism was analyzed.The use of anhydrous ethanol after stripping of g-C3N4 has the best photocatalytic performance in the simulated sunlight degradation rate of rhodamine 1.5 times before stripping.2.The g-C3N4/Bi2WO6 composite photocatalyst with lamellar flake structure was prepared by one-step hydrothermal synthesis.The morphology of the catalyst was characterized by XRD,SEM,FE-SEM,TEM,HRTEM,FT-IR and DRS.Structure and optical properties of the composites were studied systematically.Based on the crystal structure parameters,the structural models of g-C3N4 and Bi2WO6 were constructed.On the basis of this,the growth mechanism of the materials was speculated.Under the simulated sunlight,Rhodamine B explored the photocatalytic properties of the material,in which the ratio of 20% g-C3N4/Bi2WO6 showed a relatively stable flake structure,and its photocatalytic degradation rate was 3.6 times that of pure Bi2WO6.3.A different proportion of g-C3N4/Bi2S3 composites were prepared by controlling the dosage of g-C3N4 by using one-step solvothermal method using Bi（NO3）3·5H2O,thiourea and g-C3N4 as raw materials.The samples were characterized by XRD,SEM,TEM,FT-IR and UV-Vis DRS.The photocatalytic activity of the samples under simulated sunlight was studied.The mechanism of the growth of the samples and the mechanism of photocatalytic reaction were also discussed.The ratio of 20% g-C3N4/Bi2S3 composites has the best adsorption and photocatalytic properties. |
