Photocatalytic reactions can degrade almost all organic contaminants such as alkanes, halogenated alkanes, alcohols, carboxylic acids, alkenes, aromatic hydrocarbons, halogenated aromatic compounds, polymers, insecticides, herbicides, dyes and brominated flame retardants. Contaminants such as disinfection by-products. Therefore, photocatalysis technology is considered to be an ideal new technology for environmental management and a most promising means of controlling environmental pollution.

In the field of inorganic semiconductor materials, cadmium sulfide is a typical semiconductor. The CdS photocatalyst has a band gap of 2.4 eV at room temperature, and the conduction band potential (-0.87 eV) and valence band potential (1.5 eV) can meet the conditions of complete photolysis of water. . Therefore, cadmium sulfide can improve the utilization of sunlight and become one of the most attractive semiconductor catalysts in sulfide systems.

Hydrogen reacts with oxygen to form water, which does not pollute the environment. It is a clean energy and can also be used in chemical production processes such as ammonia synthesis. Electrochemical catalytic is a major method of hydrogen production. However, precious metal materials represented by platinum-based metals are expensive and have a small amount of resource storage, which limits the development of electrocatalytic hydrogen production.

Tungsten oxide is an n-type semiconductor and is a typical transition metal oxide. As a functional material, it is applied to industrial catalysts, electrochromic, battery electrodes, solar energy absorbing materials, invisible materials, gas sensing materials, and the like. Especially in the field of oxide semiconductor gas sensor applications, tungsten oxide-based materials have been considered as one of the most promising new oxide gas sensing materials for detecting NOx, SOx, NH3 and H2S.