Preparation Of Micro/Nano Structure Molybdates And Their Physicochemical Properties

As an important part of the development of nanotechnology,the controllable fabrication of nanomaterials is the cornerstone for researching the properties and applications of nanomaterials.The scheelite structure molybdate micro-nano material has excellent physical and chemical properties,which makes it widely used in light,electricity,magnetism,heat and other related fields and has potential social value.In this dissertation,the synthesis of micro-nanostructure molybdate functional materials was studied based on liquid phase chemical method,and the effect of synthesis parameters on the morphology and structure of the product is studied.The interaction between morphology and structure and their physical and chemical properties is discussed.relationship.The research content of this paper mainly consists of the following three sections:(1)A coil-ball-like CaMoO₄hierarchical structure was prepared using a simple solvothermal method without using surfactants and templating agents.XRD,SEM and other test methods were used to characterize the morphology and composition of the sample;the band gap width of the CaMoO₄samples prepared under different conditions can be measured using solid ultraviolet-visible diffuse reflection spectroscopy(UV-vis);the room-temperature photoluminescence properties of the synthesized CaMoO₄layered structure were analyzed,and the relationship between the PL properties of CaMoO₄samples and their morphology and structure was investigated.In addition,the formation process of the layered spherical CaMoO₄layer structure was also discussed.(2)Using barium chloride(Ba Cl₂·2H₂O)and ammonium molybdate((NH₄)₆Mo₇O₂₄·4H₂O)as raw materials,using a simple solvothermal method,without adding any organic additives,only by adjusting the experimental parameter of reaction time,a flower-like hierarchical structure of BaMoO₄can be synthesized.In addition,the role of reaction time in the formation and micro-morphology of the samples was also studied in detail,and the best conditions for preparing the flower-like BaMoO₄layered structure were obtained;the powders were characterized by XRD,SEM and other analytical techniques;and the solid ultraviolet-visible diffuse reflection spectrum was used(UV-vis)and fluorescence spectrum(PL)analysis preliminary evaluated the optical properties of flower-like BaMoO₄crystallites.(3)A nest-like SrMoO₄hierarchical structure was synthesized by using a solvothermal method using a mixed solution of deionized water and N,N-dimethylacetamide as a solvent and adjusting the reaction parameters.The samples were analyzed by XRD,SEM,UV-Vis diffuse reflectance spectrum,fluorescence spectrum,etc.,and the formation process of the sample and the change of its morphology were initially obtained,the formation mechanism of the nest-like SrMoO₄hierarchical structure.In addition,the photocatalytic performance of SrMoO₄samples was studied by degrading the organic pollutant rhodamine B.