Yellow tungsten oxide, also known as tungsten trioxide or WO3, can be made into an electrochromic film and used to produce an all-solid-state electrochromic device. Wherein, the discoloration mechanism of the WO3 film can be explained by the Schirmer model, that is, the small polaron model. That is because the scientists found that the small polaron model not only fits well with the WO3 light absorption curve, but also explains the phenomenon of spectral blue shift in the WO3 evaporation process.

Tungsten trioxide powder for electrochromic device is an electrochromic metal oxide. Experts say that almost all electrochromic oxides have a BO6 configuration. The figure below shows a unit cell of ABO3 perovskite lattice structure.

Tungsten oxide can be used to prepare an all-solid-state electrochromic device. It indicates that the raw material tungsten oxide powder with good electrochromic properties has met the following two basic requirements:

Yellow tungsten oxide, or tungsten trioxide, is an inorganic electrochromic material. Wherein, tungsten trioxide powder can be mainly made into an electrochromic film of amorphous structure or of crystalline structure, and then be used to assemble electrochromic devices such as smart windows. So, do you know what the difference is between amorphous WO3 electrochromic film (a-WO3 film) and crystalline WO3 electrochromic film (c-WO3 film)?