Nano grain size yellow tungsten oxide may be applied for producing thermal insulation film and therefore be used in automobiles or buildings. The heat-insulating film not only has the characteristics of high heat insulation when it is applied in cars, but also reduces the glare and beautifies your car. In a word, it makes you travel in comfort. And when such thin film is used in building glass, it has similar dings.
Yellow tungsten oxide (WO3) also has gaschromic property, which is often explained by polaron models. How does gaschromism occur? Taking hydrogen molecules as an example, hydrogen molecules are chemically decomposed on the surface of a catalyst, such as Pt; then, H diffuses and migrates along the pores of the film; react with WO3 to generate polarons and H2O, H2O escapes, and the electron transition of polarons, from a lattice (W5+) to another lattice (W6+), causes light absorption, resulting in the occurrence of gaschromism.
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