Tungsten trioxide is used for many purposes in everyday life. It is frequently used in industry to manufacture tungstates for x-ray screen phosphors, for fireproofing fabrics and in gas sensors. Due to its rich yellow color, WO3 is also used as a pigment in ceramics and paints. In recent years, tungsten trioxide has been employed in the production of electrochromic windows, or smart windows. These windows are electrically switchable glass that change light transmission properties with an applied voltage. This allows the user to tint their windows, changing the amount of heat or light passing through. Another new use for tungsten is in Dense Inert Metal Explosives, the first notable use of these devices was during the 2008–2009 Israel–Gaza conflict. 2010- AIST reports a quantum yield of 19 % in photocatalytic water splitting with a cesium enhanced tungsten oxide photocatalys.
Tungsten trioxide, yellow powder. Insoluble in water, soluble in alkali, slightly soluble in acid. It is used to make high melting point alloys and hard alloys, tungsten wires, fireproof materials, etc. It can be obtained by adding acid after co-melting tungsten ore and soda ash.
The structure of tungsten trioxide depends on temperature. It is a tetragonal crystal system above 740°C, an orthorhombic crystal system at 330-740°C, a monoclinic crystal system at 17-330°C, and a triclinic crystal system at -50-17°C. The monoclinic structure is the most common, and its space group is P21/n.
Tungsten trioxide is mainly used for calcination and reduction to produce tungsten powder and tungsten carbide powder and then for making cemented carbide products, such as manufacturing knives and molds. At the same time, it can also be used to manufacture pure tungsten products, tungsten bars, tungsten wires, and tungsten electrodes; and used as counterweight and radiation shielding materials. There is also a small amount of colorant used as a colorant for yellow ceramics in industrial production. Tungsten oxide is used as an essential anti-corrosion paint and coating material in the shipbuilding industry.
Operation precautions: airtight operation, local exhaust. Prevent dust from being released into the workshop air. Operators must undergo special training and strictly abide by the operating procedures. It is recommended that operators wear self-priming filter dust masks, chemical safety protective glasses, rubber acid and alkali-resistant clothing, and rubber acid and alkali-resistant gloves. Avoid generating dust. Avoid contact with bromine pentafluoride and chlorine trifluoride. Equipped with leakage emergency treatment equipment. Empty containers may be harmful residues.
Precautions for storage: Store in a cool, ventilated warehouse. Keep away from fire and heat sources. Keep out of direct sunlight. The package is sealed. It should be stored separately from bromine pentafluoride and chlorine trifluoride and should not be held together. Storage areas should be equipped with suitable materials to contain spills.