Tungsten trioxide may be applied for the production of heat insulation coating. So, it can be used for manufacturing various kinds of heat-insulating films with excellent weather resistance and long working life. And thus it has a great application prospect in building energy efficiency for energy saving, such as auto film, window film, and so on.
Small Polaron Model of Tungsten Trioxide
The small polaron model assumes that the spectral absorption is due to polaron transitions between two tungsten atoms (W5+ and W6+). The injected electrons are locally localized at the W5+ position, which polarize the surrounding lattice to form small polarons. And the incident photons are absorbed by these polarons, changing from one state to the other, briefly indicated as follows:
tungsten-trioxide-small-polar-submodel-image
The adjacent transition of small polarons is basically consistent with the band-to-band transition of the double charge injection/extraction model. Now more researchers have adopted the coloration mechanism of adjacent transitions.
More details, please visit:
http://www.tungsten-powder.com/Tungsten-Trioxide.html
