Boron nitride

Boron nitride
Magnified sample of crystalline hexagonal boron nitride
Names
IUPAC name
Boron nitride
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.030.111 Edit this at Wikidata
EC Number
  • 233-136-6
216
MeSH Elbor
RTECS number
  • ED7800000
UNII
  • InChI=1S/BN/c1-2 checkY
    Key: PZNSFCLAULLKQX-UHFFFAOYSA-N checkY
  • InChI=1S/B2N2/c1-3-2-4-1
    Key: AMPXHBZZESCUCE-UHFFFAOYSA-N
  • InChI=1S/B3N3/c1-4-2-6-3-5-1
    Key: WHDCVGLBMWOYDC-UHFFFAOYSA-N
  • InChI=1/BN/c1-2
    Key: PZNSFCLAULLKQX-UHFFFAOYAL
  • B#N
Properties
BN
Molar mass 24.82 g/mol
Appearance Colorless crystals
Density 2.1 g/cm3 (h-BN); 3.45 g/cm3 (c-BN)
Melting point 2,973 °C (5,383 °F; 3,246 K) sublimates (c-BN)
Insoluble
Electron mobility 200 cm2/(V·s) (c-BN)
1.8 (h-BN); 2.1 (c-BN)
Structure
Hexagonal, sphalerite, wurtzite
Thermochemistry
19.7 J/(K·mol)[1][2]
14.8 J/K mol[1][2]
−254.4 kJ/mol[1][2]
−228.4 kJ/mol[1][2]
Hazards
GHS labelling:
GHS07: Exclamation mark
Warning
H319, H335, H413
P261, P264, P271, P273, P280, P304+P340, P305+P351+P338, P312, P337+P313, P403+P233, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g. sodium chlorideFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
0
0
0
Related compounds
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

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. The cubic (zincblende aka sphalerite structure) variety analogous to diamond is called c-BN; it is softer than diamond, but its thermal and chemical stability is superior. The rare wurtzite BN modification is similar to lonsdaleite but slightly softer than the cubic form.[3]

Because of excellent thermal and chemical stability, boron nitride ceramics are used in high-temperature equipment and metal casting. Boron nitride has potential use in nanotechnology.

  1. ^ a b c d for h-BN
  2. ^ a b c d Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). Boca Raton, FL: CRC Press. p. 5.6. ISBN 1-4398-5511-0.
  3. ^ Brazhkin, Vadim V.; Solozhenko, Vladimir L. (2019). "Myths about new ultrahard phases: Why materials that are significantly superior to diamond in elastic moduli and hardness are impossible". Journal of Applied Physics. 125 (13): 130901. arXiv:1811.09503. Bibcode:2019JAP...125m0901B. doi:10.1063/1.5082739. S2CID 85517548.