ZnO Nanomaterials Preparation And The Study On Photocataiytic Oxidation And Antibacterial Performance

In this study,ZnO quantum dots were prepared by organic liquid phase synthesis.The ZnO nanostructures synthesized by different conditions were characterized by HRTEM,XRD and XPS.The photocatalytic oxidation of dye wastewater and photocatalytic sterilization experiments were carried out with synthetic ZnO materials.The following conclusions were drawn:（1）Zn O quantum dot size between 4-8nm,high purity,but the agglomeration phenomenon is more serious.The nano-materials have good photocatalytic degradation effect,and the self-made active yellow dye wastewater with initial concentration of 100mg/L is treated with 0.1 g of the best raw material ratio n(Zn²⁺):n（OH^-）=1:5 for 10min,Chroma degradation rate reached 84.5%.Calcination can effectively improve the agglomeration of ZnO quantum dots,but at the same time the particle size also appears to grow.（2）The small amount of Mg doping can reduce the agglomeration of ZnO quantum dots and enhance the surface activity of ZnO quantum dots.When the Mg doping content is 0.10%,the photocatalytic effect is the best.The chroma and COD degradation rate of 0.1 g photocatalyst 40 min to 100 mg/L active yellow dye wastewater were 92.41%and 54.55%,respectively,which were 7.91%and 10.17%respectively compared with undoped ZnO quantum dots.（3）ZnO quantum dots and Mg-doped ZnO quantum dots have good bactericidal effect.A small amount of Mg doping can improve the photocatalytic performance of ZnO quantum dots.The bactericidal rates of Escherichia coli and Staphylococcus aureus were 78.4%and 83.4%respectively at 30 min after irradiation with Mg-ZnO quantum dots at 365 nm,respectively,compared with those without Mg doping 11.2%and 12.9%respectively.Ultra-thin slice characterization showed that the bactericidal mechanism was mainly photocatalytic oxidation and dissolution of metal ions.