Characteristic
Boron nitride is a thermally and chemically resistant refractory compound of boron and nitrogen with the chemical formula BN. It exists in various crystalline forms that are isoelectronic to a similarly structured carbon lattice. The hexagonal form corresponding to graphite is the most stable and soft among BN polymorphs, and is therefore used as a lubricant and an additive to cosmetic products.
Chemical formula:BN
Molar mass:24.82 g·mol−1
Appearance:Colorless crystals
Density:2.1 (h-BN); 3.45 (c-BN) g/cm3
Melting point:2,973 °C (5,383 °F; 3,246 K) sublimates (cBN)
Solubility in water:insoluble
Electron mobility:200 cm2/(V·s) (cBN)
Refractive index (nD):1.8 (h-BN); 2.1 (c-BN)
Crystal structure:hexagonal, sphalerite, wurtzite
Application
Because of excellent thermal and chemical stability, boron nitride ceramics are traditionally used as parts of high-temperature equipment. Boron nitride has potential use in nanotechnology. Nanotubes of BN can be produced that have a structure similar to that of carbon nanotubes, i.e. graphene (or BN) sheets rolled on themselves, but the properties are very different.