Tungsten trioxide (WO₃) is an important n-type semiconductor oxide, which has a variety of crystal structures. Due to its unique physical and chemical properties, it has been widely studied, and has been applied in electrochromic, photochromic, sensing and catalytic fields. In order to further utilize the excellent properties of WO₃ and broaden its application field, the best technical way is to reduce its grain size, that is, nano tungsten oxide.

WS₂ and reduced graphene oxide (WS₂/rGO) nanocomposite is prepared by in situ reduction of graphene oxide. This kind of material has good catalytic activity for hydrogen evolution as well as high sodium storage capacity. It can be widely used in many fields such as supercapacitor, Na-ion battery and so on.

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.

Tungsten disulfide is not only a kind of solid lubricating material with high quality, but also a catalyst with good activity. It is widely used in lubrication material,  piezoelectric material and other important fields, which is closely related to some of its properties.