Tungsten oxide is also called tungsten trioxide, including yellow tungsten oxide (YTO, WO3), blue tungsten oxide (BTO, WO2.9), violet tungsten oxide (VTO, WO2.72or W18O49) and brown tungsten oxide(tungsten dioxide, WO2).
Tungsten oxide is a chemical compound containing oxygen and the transition metal tungsten. It is obtained as an intermediate in the recovery of tungsten from its minerals.Tungsten ores are treated with alkalis to produce WO3. Further reaction with carbon or hydrogen gas reduces tungsten trioxide to the pure metal.Tungsten oxide is obtained from the minerals scheelite, wolframite, ferberite. It is insoluble in H2O and acids, but soluble in hot alkalis.
Tungsten oxide has good physical and chemical properties, so it can be widely applied in many different fields. The fine tungsten oxide has strong absorption capacity on electromagnetic wave, so it can be used as perfect absorbing material in solar system applications and important invisible material in military field. Also it has good catalytic property, so it can be used as catalytic materials in the anode electrode of fuel cells. It can also be applied as low temperature superconducting materials. After mixed with TiO2, it can be used as photocatalyst.Tungsten oxide is unstable with NOX, H2S and NH, thus it is used as sensitive material for tranducer and test food, pharmaceuticals, off-gas.