Yellow tungsten oxide, blue tungsten oxide and violet tungsten oxide difference is caused by their oxygen content, mainly reflecting in appearance, molecular formula and boiling point and other properties, some properties of YTO, BTO and VTO are shown as follows:
1. Yellow tungsten oxide is lemon yellow crystalline powder, with its density of 7.2~ 7.4g/cm3, melting point of about 1470℃, boiling point among 1700~2000℃, which is significantly sublimation at 800 ℃;
2. Blue tungsten oxide with 2.9 oxygen molecules, and shows in blue or dark blue crystals powder, with the formula of WO2.9, the english abbreviation for BTO or TBO;
3. Violet tungsten oxide is short for VTO, purple finely crystalline powder, formula of WO2.72or W18O49, which is generated by precise controlling the reduction temperature in the production process of ammonium paratungstate (APT).
Yellow tungsten oxide, blue tungsten oxide and violet tungsten oxide difference is shown as the picture bellow: