Amorphous WO3 Film

Amorphous WO3 film has an electrochromic effect, according to experts. As the structure of the thin film is relatively loose, it is advantageous for lithium ion insertion and extraction. However, they also found that in the cyclic discoloration, the structure of the film was gradually destroyed. After 200 cycles, the optical modulation amplitude was reduced from 48.0% to 3.0%, and WO3 turned brownish yellow, so it is impossible to realize the circulation of color change.

amorphous WO3 film image

More details, please visit:
http://www.tungsten-powder.com/tungsten-oxide.html

amorphous WO3 film picture

The electrochromic effect of tungsten oxide was discovered by Deb in 1973. He thus proposed the electrochromic "oxygen vacancy color center" model, which is also known as the color center model. At the time, he was studying amorphous tungsten oxide films. Specifically, how does Deb think? Deb believes that the highly incomplete crystal structure of amorphous tungsten oxide results in a large number of positively charged oxygen vacancy defects in the film. The positively charged oxygen vacancy defect captures the electrons from the cathode into the tungsten oxide film to form an F color center. The trapped electrons transition to the conduction band after absorbing the photon energy of the visible light, thereby changing the tungsten oxide film from transparent to blue. When the polarities of the applied electric field changes, the injected electrons are extracted from the film, the color center disappears, and the film fades.

 

WeChat