Construction And Photocatalytic Performance Of 0D/2D Bi₁₂O₁₇Cl₂

In recent years,semiconductor oxidation technology has shown obvious advantages in solving environmental pollution problems.Photocatalyst itself is non-toxic,harmless,non-corrosive,but also can be recycled,reused;It can completely mineralize organic pollutants into inorganic ions without secondary pollution.It is a widely used green environmental governance technology.Among all the photocatalysts,Bi₁₂O₁₇Cl₂ has excellent optical properties,photoluminescence and photocatalytic properties due to its unique layered structure.Therefore,Bi₁₂O₁₇Cl₂ has a good ability to degrade pollutants and selectively oxidize by visible light.However,due to its large charge hole coincidence rate and low visible light absorption range,Bi₁₂O₁₇Cl₂shows unsatisfactory photocatalytic performance.Therefore,experts and scholars adopt various methods to modify the original Bi₁₂O₁₇Cl₂to promote Bi₁₂O₁₇Cl₂to degrade various pollutants more efficiently under visible light.However,these methods are not economical and simple enough.Therefore,in this paper,two simple and economical strategies were used to modify Bi₁₂O₁₇Cl₂with two-dimensional sheet morphology and form composite materials,so as to improve the photocatalytic performance of Bi₁₂O₁₇Cl₂:（1）Fe/Bi₁₂O₁₇Cl₂ nanocomposites were successfully prepared by wet impregnation with Fe NO₃ and 2D layered Bi₁₂O₁₇Cl₂ as raw materials.The amorphous Fe（Ⅲ）clusters with the particle size of10-20nm are uniformly distributed on the surface of the two-dimensional thin layer of Bi₁₂O₁₇Cl₂,and there is a good interfacial contact between them,which can effectively improve the visible light absorption capacity of the sample.When the composite material is used for photocatalytic degradation of Rhodamine B organic pollutants,the degradation rate of the optimal sample proportion is about 2.1 times that of the single Bi₁₂O₁₇Cl₂,and the sample has good recycling ability.The enhanced photocatalytic performance of the composites can be attributed to the good interface contact between the two materials with different dimensions,which promotes the charge transfer.·O^2-and H⁺are the main active species in the degradation process of composites.Finally,a possible photocatalytic reaction mechanism is deduced.（2）0/2 dimensional Cd S/Bi₁₂O₁₇Cl₂ composites were prepared by two methods（one-step hydrothermal method and photodeposition）.The0-dimensional Cd S and Bi₁₂O₁₇Cl₂ form stable heterojunction structure,which can promote the photoabsorption ability and photoelectron migration ability of the catalyst.The photocatalytic degradation of rose was 3.2 times better than that of Bi₁₂O₁₇Cl₂,and showed stable photocatalytic activity.Therefore,a Z-mechanism is proposed based on the position of the active group and the conduction band of the valence band.