As an important n-type semiconductor oxide, tungsten trioxide (WO₃) is widely used in chemical sensors, photocatalysis, energy conversion systems and other fields. Because of its large theoretical capacity (693 mAh/g), low cost and high safety (high melting temperature and mechanical stability), tungsten trioxide can also be used as negative electrode materials for lithium ion batteries.

Quantum dots (QDs) are a new kind of nano-fluorescent materials. Because of their unique electrical and optical properties, QDs have been widely used in physics, chemistry, biology and other fields. As a new fluorescent material.

At present, the existing processes for recovering and treating waste tungsten oxide to produce ammonium tungstate solution, ammonium paratungstate and ammonium metatungstate are all based on the chemical properties of all tungsten trioxide and blue tungsten oxide which are insoluble or slightly soluble in ammonia water and only soluble in caustic soda or soda ash. The process is to dissolve oxygen in normal pressure or pressure boiling with caustic soda (sodium hydroxide) solution or soda carbonate solution in advance. Tungsten carbide is prepared into sodium tungstate solution, or tungsten oxide is melted with sodium carbonate at high temperature, then tungsten is boiled and leached to form sodium tungstate solution.

Nitrogen oxide (NO_x), as a highly toxic gas, is the main source of acid rain and photochemical smog, which has posed a serious threat to human health and safety. Therefore, the detection of nitrogen oxides has become a research hotspot in recent years.

In industrial production, hydrogen, as a non-polluting green energy, has attracted wide attention. However, hydrogen is volatile, low ignition point, colorless and tasteless. It is a very dangerous flammable gas when it encounters open fire when its concentration in air is 4-75%. Therefore, the monitoring technology and research of gas sensitive materials for hydrogen play an important role in ensuring personal and property safety.

Hydrogen sulfide is a colorless gas with the odor of rotten eggs. Its toxicity is very strong. Its permissible concentration in the air is 10 ppm. The upper and lower limits of explosion range from 4.3% to 46.0%. The harm of hydrogen sulfide gas to human body belongs to chemical nerve toxicity, stimulation and asphyxiation gas, which can destroy red blood cells and cause olfactory stimulation at 0.1 ppm. Therefore, how to quantitatively detect trace hydrogen sulfide gas in the air has become an urgent problem to be solved in relevant workplaces.

Tungsten oxide resistance memory is a semiconductor device which can achieve storage by reversible change of resistance value of tungsten oxide material under electric field.

In recent years, flexible perovskite solar cells have attracted much attention, and the flexible substrates used have a great impact on the performance of devices. At present, the commonly used flexible substrates of polyethylene terephthalate (PET) and metal foil can not meet the demand. It is urgent to find a cheap and abundant new flexible substitutes.

Tungsten oxide is a new functional material, which can be used in chemical sensors, catalytic materials, electrochemical electrodes, electrochromic materials, high temperature superconducting materials, solar energy absorbing materials, wave absorbing stealth materials and so on.

At present, tungsten trioxide has been used in many aspects of daily life, such as the manufacture of X-ray phosphors, refractories and gas sensors. In addition, tungsten trioxide has an important application field, namely photocatalytic degradation materials.