Cathode materials have been the bottleneck to improve the performance and reduce the cost of lithium-ion batteries. Lithium iron phosphate is the first choice of cathode materials for modern commercial lithium-ion batteries because of its low price, high energy density, long life and good safety. However, the low electronic conductivity of lithium iron phosphate seriously hinders its application in the field of power and energy storage batteries.

Tungsten disulfide (WS₂) is a kind of layered solid lubricant with structure similar to graphite. It has excellent high temperature resistance, extreme pressure resistance, good adsorption capacity on metal surface and low thermal conductivity. WS₂ was first applied to the lubrication of the key parts of the American mariner spacecraft, and it was used to prepare high temperature extreme pressure grease and energy-saving engine lubricating oil, with good application results.

At present, China's major cities are booming in the construction of rail transit projects. Because of its unparalleled advantages, shield method has been widely used in the construction of rail transit tunnels.

Rare earth trivalent ions have rich 4f energy level configuration, and their fluorescence characteristics are greatly affected by the crystal field environment and the symmetry of the lattice. At present, many scholars use the small size effect of semiconductor nano materials (ZnO, TiO₂) and lattice sensitization to improve the optical properties of rare earth trivalent ions, which are widely used in biological fluorescent probes, optical devices and new luminescent materials.

For electronic and photoelectric applications, solar cells convert energy from sunlight to electricity. Graphene has excellent charge transfer performance. Electrons move in graphene at 1 / 30 of the speed of graphite - much faster than other materials. This shows that graphene can be used in solar cells, but graphene also has a major disadvantage, which hinders this application - its ultra short life excited electrons are only about one picosecond (one millionth of a second).

With the continuous exploitation of tungsten resources, scheelite and medium ores with high impurity content become the main sources of tungsten smelting raw materials. In the existing technology, the smelting of Scheelite Concentrate and medium ore generally adopts the high alkali pressure boiling technology, and the alkali input is generally 2.8-4 times of the theoretical amount. The quality ratio of excess NaOH and WO₃ in the coarse sodium tungstate solution obtained after the alkali pressure boiling slurry is 0.7-1.2. If not recovered, it will not only bring adverse effects on the subsequent process, but also consume sulfuric acid to neutralize it before discharging.

Nano WO₃ has a strong absorption capacity for electromagnetic wave. It can be used as an excellent absorption material in the utilization of solar energy and an important invisible material in the military. It also has a huge specific surface area and remarkable surface effect. It has been widely used in fuel cells, chemical sensors, optoelectronic devices and other fields.

Metal oxides play a key role in the development of many advanced functional materials and smart devices. Among many metal oxides, tungsten trioxide (WO₃) is a kind of unique material, which has attracted much attention due to its versatility. For example, WO₃ is an n-type semiconductor with various crystal forms, band gap width of 2.5-2.8ev, and visible light response characteristics. Therefore, WO₃ can be used as light sensing device, photochromic device, transparent electrode, visible light catalyst, etc.

Tungsten oxide is a typical transition metal oxide with a band gap of 2.4-2.8ev, which belongs to a typical n-type semiconductor. In addition to catalysis, electrochromism, battery electrode, solar energy absorbing material and invisible material, tungsten oxide also has the properties of semiconductor functional materials such as pressure sensitive, thermal sensitive and gas sensitive.

The preparation of core-shell nanocomposites is mainly divided into several methods, such as interface polymerization, condensed phase separation, drying bath and sol-gel method.