What is Violet Tungsten Oxide?

Violet tungsten oxide of a dark purple to pure purple color is one of the four stable oxides of tungsten. It is composed of tungsten copper, tungsten trioxide and other different components. And the components and their quantities depend on the specific preparation method.

Structure of VTO

Violet tungsten oxide has a unique needle structure. It is loose cluster composed of needle like or rod like grains. And there are abundant cracks inside the cluster. Due to this unique structure with large gap, violet tungsten oxide has low apparent density, which helps the infiltration of hydrogen and the evolution of water vapor. Moreover, it makes the reduction reaction occur not only on violet tungsten oxide surface but the interior. Compared with yellow tungsten oxide and blue tungsten oxide, violet tungsten oxide has the highest chemical activity and the fastest rate of hydrogen reduction.

Properties of VTO

1. Reducibility

2. High chemical activity

3. Good absorption property of ultraviolet and near-infrared light

4. Excellent electrochromic performance

5. Good low temperature resistance

6. Good thermal insulation

Application of VTO

1. It is an important raw material to produce ultrafine tungsten powder and tungsten carbide powder with good dispersibility.

2. It is used to prepare near-infrared shielding materials, infrared absorbers, fuel cells (lithium batteries), etc.;

3. It is applied to prepare electrochromic film, electrochromic glass, etc.;

4. It is used to prepare thermal insulation masterbatch, thermal insulation mortar and many other thermal insulation materials.

Preparation of VTO

1. VTO can be prepared by calcine ammonium tungstate under precise control of temperature. And the size of violet tungsten oxide particle is affected by the raw material directly.

2. VTO can be prepared by calcining ammonium metatungstate.

3. VTO can be prepared by reducing tungsten trioxide or blue tungsten oxide in presence of hydrogen.

4. VTO can be prepared by calcining tungsten powder and tungsten trioxide in presence of argon.

• < Prev
• Next >