# Tungsten trioxide, WO3

Tungsten trioxide (WO3) is a compound of tungsten and oxygen that presents as a yellow, inorganic solid in its pure form. It has notable photochromic properties, meaning it can change color upon exposure to light. Due to this unique characteristic, WO3 has been explored for use in smart windows that can modulate the amount of light they let through based on external conditions. Additionally, it's an essential material in the field of electrochromism, with potential applications in electrochromic devices like smart windows and displays. Tungsten trioxide is also used as a precursor for the synthesis of other tungsten compounds and is employed as a raw material in the production of tungsten metal. Furthermore, it plays a role in catalysis, particularly in processes that involve the oxidation of volatile organic compounds.

## Other names

- Tungstic anhydride
- Tungsten(VI) oxide
- Tungsten oxide
- Tungstic oxide
- Trioxotungsten

## External links

- Tungsten trioxide - Wikipedia
- Tungsten trioxide - PubChem
- Tungsten trioxide - NIST Chemistry WEbbook