3D Structure Of Graphene Oxide/Transition Metal Dichalcogenides/Mg-doped ZnO Composite

In recent years,ZnO-based materials have played an important role in sewage treatment,environmental protection,hydrogen production by water-splitting and solar cells and so on.Graphene is a kind of outstanding support due to high specific surface area and excellent photoelectric properties.Graphene as support can enhance the dispersibility,adsorption and catalytic activity of ZnO nanomaterials.However,graphene cannot give full play to excellent physical and chemical properties because of the aggregation,curl and poor compatibility with other material in the process of synthesis.In addition,graphene itself has no photocatalytic activity and can only support and disperse other catalyst as support.Therefore,it has attracted the attention of science and technology workers,about how improved the enhancement effect of graphene.Graphene oxide(GO)show better dispertion performance and stonger chemical activity than graphene on account of the abundant surface functional groups.Whereas,the structure defects reduced the electrical conductivity.To improve the dispersion,electrical conductivity and make GO possessing better photocatalytic activity,the 3D GO/transition metal dichalcogenides(WS2,MoS2)composite support are made by electrostatic interactivition.The 3D GO/TMDs composite support can not only effectively inhibite the aggregation and curl of GO,but also increase the specific surface area and adsorption of composites.Moreover,because of forming "synergistic effect" between GO and TMDs,3D GO/TMDs composite support is becoming a research highlight.In this paper,on the basis of the surface modication,we constructed the GO/TMDs composite support with synergistic effect by electrostatic attraction,and then obtained 3D GO/WS2/Mg-ZnO composite catalyst(GWMZ)and GO/MoS2/Mg-ZnO composite catalyst(GMoMZ)via layer-by-layer assembly method.We also analyed the stucture and morphology of composite catalyst,and discussed the synthetic mechanism and enhancement mechanism of photocatalytic activity.We obtained a novel kind photocatalyst with visible light photocatalytic activity by decracting the Mg-ZnO nanoparticles on the 3D GO/TMDs composite support surface,and the 3D GO/TMDs enhanced the photocatalytic activity and antibacterial activity of Mg-ZnO nanoparticles.The paper has important theoretical guiding signficance and application value,also provide a simple and effective method for the design of 3D graphene composite nano material.The main findings were exhibited as follows:(1)Using GO,WS2 nanosheets,zinc acetate,magnesium acetate and oxalic acid as rawmaterials,deionized water as solvent,the 3D GWMZs were synthesized by coprecipitation and subsequent heat treatment.The effect of synthetic process to structure and morphology of obtained samples were characterized,such as SEM,TEM,XRD,BET,TG-DTA,Raman,PL,UV-vis,XPS and ESR.Furthermore,we studied the photocatalytic activity and durability,antibacaterial activity of GWMZ,and discussed the assembly and enhancement mechanism of GWMZ.The results show that the 3D GO/WS2 composite support were obtained by electrostatic assembly,and the Mg-ZnO nanoparticles were decracted on the 3D GO/WS2 composite support surface by.The introduction of WS2 nanosheets can improve the specific surface area,induce many defects on the surface of GO,enhance the photocatalytic activity of GO/Mg-ZnO composite material.Simultaneously,the "synergistic effect" between GO and WS2 can develop the conductivity and specific capacitance,obtaining GWMZs composite with high photocatalytic activity,durability and antibacaterial activity.When the WS2/GO wt.%= 20.8%,GW/MZ wt.‰ = 6.9%and the heat treatment temperature is 500 ?,the GWMZ shows the best photocatalytic activity,90%Rh B was degraded within 15 min under UV light and 90 min under visible light.(2)The 3D GO/MoS2 composite support were obtained by electrostatic attraction,and the 3D GMoMZs were synthesized by coprecipitation and subsequent heat treatment.The effect of MoS2/GO wt.%to structure and morphology,photocatalytic activity of obtained samples were studied.The results show that the specific surface area and the visible light utilization of GO/Mg-ZnO composite material were enhanced due to the "synergistic effect" between GO and MoS2.Under the simulated sunlight,the GMoMZ can degrade 98%Rh B was within 98 min was twice of GMZ.In addition,The introduction of MoS2 nanosheets decrease the resistance and increase the specific capacitance and the ability to store photoproduction electronic.