Violet tungsten oxide may be used to prepare an all-solid-state electrochromic smart window, which is also known as an energy-saving window. Now, such window is widely used in the heat insulation fields of buildings, automobiles, airplanes and spacecraft.

Nano tungsten oxide, as a nano-inorganic electrochromic material, can be a main component of water-based heat insulation glass coating. Tungsten oxide nano powder has unique optical properties, that is, ideal selectivity to the solar spectrum, so it has become the best material for solving the thermal insulation problem in semiconductor materials.

Phosphotungstic acid is an extremely important raw material for producing a thermal insulation film. For example, it can be used to prepare a photochromic material composed of an inorganic/polymer composite material. And the obtained composite photochromic material can be sprayed on the surface of the automobile window, and then sprayed with a varnish to form a window film. Due to its own environmental protection, such smart film is more and more widely applied in automobiles.

Phosphotungstic acid is an important raw material for the preparation of photochromic material such as heat insulation film. For the prepared thermal insulation film, experts said that the transparent film can prevent glare, giving the driver a clear view, ensuring the safety of driving. And it can also shield 90% of the ultraviolet rays, preventing the fading and aging of plastic items and rubber parts. In addition, the super glue of the smart film can also stick the broken glass together to prevent secondary damage to people.