Fluorescent powder has important application value in many sectors of national economy. The most widely used fluorescent lamp, followed by LED display screen. In addition, fluorescent powder can also be used on oscilloscopes and radar fluorescent screens, as well as electronic-photon converters, nuclear radiation displays and X-ray sensitization screens. In short, the use of fluorescent powder is extensive, and its scope of use is expanding year by year.

Vehicle exhaust contains a lot of nitrogen oxides. It not only causes acid rain, photochemical smog and other environmental problems, but also seriously threatens human health. Therefore, how to remove nitrogen oxides efficiently has become an important topic.

Nanostructured materials have unique physical, chemical, electrical, magnetic and mechanical properties and have potential applications in filling materials, drug delivery, catalysis and other fields. Previous studies have shown that transition metal disulfides have unique properties and can be used as photosensitive materials, catalysts, lubricants, cathode materials for high-energy batteries, etc.

Scientists at a British university are experimenting with tungsten in a world-class new facility to help develop a new fusion reactor, ITER. ITER refers to the International Thermonuclear Fusion Experimental Reactor, which is known as the "artificial solar" project. Many countries involved in the research believe that if the "artificial sun" can be realized, it will produce almost unlimited clean energy, which is inexpensive and incalculable.

Tin dioxide is an n-type semiconductor material with good chemical stability and optical anisotropy. It is widely used in gas-sensitive materials, photoelectric materials, lithium-ion battery materials and other fields. By doping, tin dioxide can become semiconductor or conductor, improve its conductivity and spectral selectivity, and expand its application range.

Tungsten disulfide is a fine gray crystalline or powder with metallic luster. It belongs to hexagonal crystal system. It has semiconductor and diamagnetic properties, layered structure, easy dissociation, and lubricating properties similar to graphite. It is mainly used as lubricant. Its performance is better than molybdenum disulfide. Its friction coefficient is lower and its compressive strength is higher.

Transition metal oxides can be used in various fields. Molybdenum oxide and tungsten oxide, as two important transition metal oxides, have attracted the attention of scholars and experts in the fields of photocatalysis and gas sensors for a long time. In the past few years, it has been found that the properties of binary molybdenum tungsten oxide (MoxW1-xO3) materials can be greatly improved due to the "synergistic effect" of the two elements. Therefore, by changing the composition and structure of materials, we can make this "synergistic effect" play a stronger role.

Tungsten carbide is the main raw material for the manufacture of cemented carbide products, and its particle size has a decisive influence on the properties of cemented carbide products. The preparation of nano tungsten carbide has become the main way to improve the strength and toughness of cemented carbide products. Cemented carbide is brittle material. There is a contradiction between its hardness and strength. High hardness leads to low strength, while high strength leads to low hardness.

Zirconium tungstate is a special kind of negative thermal expansion material with isotropic negative thermal expansion property. It reaches thermodynamic stability in the temperature range of 1378K-1530K, and exists in metastable state at room temperature. At present, three kinds of phases have been found: low temperature cubic phase a-ZrW₂O₈, high temperature phase beta-ZrW₂O₈ and high pressure phase gamma-ZrW₂O₈. Their thermal expansion coefficients are aalpha=-8.7x10^-6/K, abet=-4.9x10^-6/K and agamma=-1x10^-6/K.

At present, the commonly used preparation methods of tungsten trioxide thin films are atomic layer deposition, chemical vapor deposition and electrodeposition. However, the tungsten trioxide thin films based on the above methods require high equipment, complex preparation process, high cost, and can not prepare large-area films. Therefore, it is imperative to develop a tungsten oxide PEC semiconductor electrode material with simple production process, low cost, high purity and high photoelectric conversion efficiency.