Preparation method of one-dimensional Euphorbia-milii-shaped WO3 microcrystal

Abstract

The invention provides a preparation method of a one-dimensional Euphorbia-milii-shaped WO3 microcrystal, which comprises the following steps: adding WCl6 into an isopropanol-distilled water mixed solvent, adding a polyoxyethylene-polyoxypropylene block copolymer into the solution to obtain a precursor solution, pouring the precursor solution into a hydrothermal kettle, and reacting while controlling the temperature at 80-240 DEG C under the pressure of 2-16 MPa for 4-36 hours, wherein the hydrothermal kettle is fixed in an homogeneous reaction instrument, and rotates around a fixed axis at the rate of 20-70 r / min in the insulating process; and taking out the product, washing and drying. The prepared one-dimensional Euphorbia-milii-shaped WO3 microcrystal has the advantages of high purity, favorable crystallinity, favorable dispersity, uniform size, uniform shape and obvious oriented growth.

Description

technical field [0001] The invention relates to a method for preparing one-dimensional tiger thorn plum-shaped WO 3 The microcrystalline method, in particular to a homogeneous nonionic surfactant-assisted solvothermal method for the preparation of one-dimensional thornberry-like WO 3 microcrystalline method. Background technique [0002] Tungsten trioxide (WO 3 ) is usually a yellow powder, insoluble in water, soluble in lye, slightly soluble in acid. It is used to make high melting point alloys and hard alloys, tungsten wires and fireproof materials, etc. When the temperature reaches 850℃, it sublimates significantly, hardly reacts with inorganic acids except hydrofluoric acid, and can be slowly dissolved in ammonia water or concentrated alkali solution. It reacts with chlorine gas to form oxychloride, but it cannot react with bromine and iodine. WO 3 The crystal structure depends on the temperature: it is a tetragonal crystal system above 740°C, an orthorhombic cryst...

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Problems solved by technology

Microemulsion method, spray drying method and acidification precipitation method all need to synthesize WO under high temperature calcination conditions. 3 , the powder is easy to agglomerate and the process conditions and structure design are difficult to control, which is very important for the preparation of WO 3 The utilization rate of the required raw materials is very small, and it is difficult to obtain one-dimensional nanomaterials grown in orientation; and the template replication technology and the sol-gel method also require post-heat treatment and crystallization process, which will also cause the agglomeration of nanocrystals, and the grains are abnormally long Large, the microstructure of the material is difficult to control

At the same time, the chemical vapor deposition method requires high equipment and the ratio of reactants is difficult to control. The prepared WO 3 Impurities are easily introduced into nanomaterials

In addition, the hydrothermal method can only react in an aqueous medium, and cannot control the polarity of the reaction solvent to control the crystallization and morphology of the product; the microwave-assisted solvothermal reaction rate is fast, the nucleation-growth rate is fast, and it is difficult to control the product oriented growth

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