Tungsten oxide (WO₃) is an indirect bandgap n-type semiconductor material with a band gap of 2.2-2.8eV. It has good absorption of visible light, so it is a very promising semiconductor photocatalyst. In common practice, metal ions are doped into semiconductor photocatalysts, and the recombination of electron-hole pairs can be significantly inhibited by IFCT effect, which can greatly improve the photocatalytic activity of photocatalysts.

Chromochromism refers to the phenomenon that the optical properties (reflectivity, transmittance, absorptivity, etc.) of materials change reversibly under the action of external electric field or voltage. Electrochromic materials have wide application prospects in smart windows, anti-glare mirrors, optical information storage and other fields.

At present, the raw materials of organic chemicals and energy industry mainly come from fossil resources such as coal, oil and natural gas. The depletion of fossil resources and the deterioration of ecological environment force people to seek new ways to synthesize chemicals and fuels from renewable resources.

Zirconium tungstate (ZrW₂O₈) is a commonly used negative expansion material, which has high coefficient of negative expansion and wide temperature range. Zirconium tungstate can be prepared separately or added to metal matrix, such as copper or aluminium alloy, to reduce the expansion coefficient of the material. However, in the modern process, excessive preparation temperature and holding time will lead to the decomposition of zirconium tungstate or the reaction between zirconium tungstate and metal, so how to control the interface reaction is also a problem that zirconium tungstate metal matrix composites need to face.