WO3 electrochromic film is a smart material that can be applied to architectural glass to obtain the so-called smart windows for thermal insulation and energy conservation. There are many methods for preparing such WO3 electrochromic film, such as, a spray method, a hydrothermal method, and an electrodeposition method.

Smart material mentioned here refers specifically to smart glass, i.e., electrochromic glass, and tungsten trioxide can be used in this new type of smart glasses. Why can WO3 be applied in building glasses for building energy efficiency?

Nano WO3 electrochromic film can be prepared by a hydrothermal method. At present, many researchers have adopted hydrothermal method to prepare nano WO3 films. However, preparation of WO3 film by hydrothermal process is complicated with cumbersome steps. And high temperature long-term reaction is often required. Also, the seed layer coated on the surface of the conductive substrate is required to be high. In addition, the preparation conditions including high temperature and high pressure limit the choice of conductive substrates.

Mo-doping tungsten oxide film can be prepared by doping molybdenum oxide (MoO3) into a tungsten oxide film. The tungsten oxide film with different MoO3 doping ratio can be prepared by electron beam evaporation method. Among them, the doping of Mo element has a certain influence on the electrochromic properties of WO3 film.