Tungsten trihydrate seed hydrothermal method, also known as high temperature solution method, including temperature difference method, cooling method. To improve the growth rate of tungsten oxide crystals, seed water and heat-assisted method generally uses dual temperature zone high pressure reactor. Mainly rely on the solution in the container to maintain the temperature convection to form a supersaturated state.

In 1969, for the first time, some scholars found the electrochromism of amorphous tungsten trioxide. Due to its high electrochromic color contrast, good cycle stability and good thermal stability, tungsten trioxide has become the most studied and commercially available inorganic electrochromic material in recent years.

Tungsten trioxide electrodeposition method refers to the tungsten oxide from its aqueous solution of compounds, non-aqueous solution or molten salt electrochemical deposition process. Metal electrolytic smelting, electrolytic refining, electroplating, electroforming process foundation.

Tungsten trioxide thin film nano-spray method to solve the hydrothermal method for the preparation of large-area film and electrodeposition deposition film stability problems. High-quality molybdenum-doped tungsten trioxide nanoparticles were prepared by a simple, green solution doping technique. These nanoparticles can be uniformly dispersed in water to form a stable nano-ink.

Tungsten oxide thin film electrochromic materials research for nearly 50 years. Tungsten trioxide thin film is the most excellent performance of inorganic electrochromic materials, and has begun to commercialize. However, the high preparation cost and long response time of the commercial tungsten trioxide film still restrict its practical application.

The ideal tungsten oxide crystal is a colorless and transparent insulator in strict accordance with the stoichiometric ratio. The chemical formula is Re O3. As shown in the figure can be seen tungsten oxide crystal structure. The ideal tungsten trioxide has a molecular weight of 231.85. The ideal density of 7.16g / cm3, the melting point of 1473 degrees Celsius, the boiling point of 1750 degrees Celsius, forbidden band width of 2.9eV. The chemical properties of tungsten trioxide at a relatively low temperature will be in a relatively stable state.

Tungsten trioxide, as an important intermediate oxide in the production of tungsten, plays an extremely important role in the production of tungsten products. Therefore, in the production of tungsten, the separation and recovery of tungsten trioxide in the spent catalyst can provide an effective solution to the related environmental problems. At the same time can also bring us considerable social benefits.

The excellent properties of tungsten alloy materials are closely related to their density. If the density of tungsten and its alloy is above 95%, if the densification is reduced by 1%, the thermal conductivity will decrease by 10%, and the mechanical properties such as hardness and tensile strength will also decrease significantly with the decrease of density.

The doped tungsten powder produced by the present method has much impurity content, or equipment investment and cost. At the same time, due to the contact of hydrofluoric acid and hydrochloric acid in the production process, the damage to the equipment is relatively large, resulting in short service life of the equipment.

Nearly 70% of the world's tungsten resources by scheelite structure. At present, with the continuous depletion of wolframite Scheelite Resources, has become the main industrial raw materials.