Cobalt(II,III) oxide

Cobalt(II,III) oxide
Cobalt(II,III) oxide
Cobalt(II,III) oxide
Ball-and-stick model of the unit cell of Co3O4
Ball-and-stick model of the unit cell of Co3O4
Names
IUPAC name
cobalt(II) dicobalt(III) oxide
Other names
  • Cobalt oxide
  • Cobalt(II,III) oxide
  • Cobaltosic oxide
  • Tricobalt tetroxide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.013.780 Edit this at Wikidata
EC Number
  • 215-157-2
RTECS number
  • GG2500000
UNII
  • InChI=1S/3Co.4O checkY
    Key: LBFUKZWYPLNNJC-UHFFFAOYSA-N checkY
  • InChI=1/3Co.4O/rCo2O3.CoO/c3-1-5-2-4;1-2
    Key: LBFUKZWYPLNNJC-PMPQCLQHAA
  • [Co]=O.O=[Co]O[Co]=O
Properties
  • Co3O4
  • CoO·Co2O3
Molar mass 240.796 g·mol−1
Appearance black solid
Density 6.07 g/cm3
Melting point 895 °C (1,643 °F; 1,168 K)
Boiling point 900 °C (1,650 °F; 1,170 K) (decomposes)
Insoluble
Solubility soluble (with degradation) in acids and alkalis
7380×10−6 cm3/mol
Structure
cubic
Fd3m, No. 227
Hazards
GHS labelling:[citation needed]
GHS09: Environmental hazardGHS08: Health hazard
Danger
H317, H334, H350, H411
P261, P273, P284, P304+P340, P342+P311
NFPA 704 (fire diamond)
[citation needed]
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 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
2
0
0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X markN verify (what is checkYX markN ?)

Cobalt(II,III) oxide is an inorganic compound with the formula Co3O4. Along with cobalt(II) oxide, it is one of two well characterized and stable cobalt oxides. It is a black antiferromagnetic solid. As a mixed valence compound, its formula is sometimes written as Co2+Co3+2O4 and sometimes as CoO·Co2O3. It occurs naturally as the rare mineral guite which is named in honor of Prof. Xiangping Gu (1964-).

Structure

Co3O4 adopts the normal spinel structure, with Co2+ ions in tetrahedral interstices and Co3+ ions in the octahedral interstices of the cubic close-packed lattice of oxide anions.

tetrahedral coordination geometry of Co(II)distorted octahedral coordination geometry of Co(III)distorted tetrahedral coordination geometry of O

Synthesis

Cobalt(II) oxide, CoO, converts to Co3O4 upon heating at around 600–700 °C (1,112–1,292 °F) in air. Above 900 °C (1,650 °F), CoO is stable. These reactions are described by the following equilibrium:

2 Co3O4 ⇌ 6 CoO + O2

Applications

Cobalt(II,III) oxide is used as a blue coloring agent for pottery enamel and glass, as an alternative to cobalt(II) oxide.

Cobalt(II,III) oxide is used as an electrode in some lithium-ion batteries, possibly in the form of cobalt oxide nanoparticles.

Cobalt(III) fluoride can be prepared from cobalt(II,III) oxide by sequential treatment with hydrogen fluoride and then fluorine gas, producing a mixture of cobalt(II) fluoride and cobalt oxyfluoride as intermediates, with overall stoichiometry:

Co3O4 + 4 HF → CoF2 + 2 CoOF + 2 H2O
2 CoF2 + 4 CoOF + 5 F2 → 6 CoF3 + 2 O2

See also

References

  1. ↑ "Cobalt(II,III) oxide 203114". Sigma-Aldrich.
  2. ↑ Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, Florida: CRC Press. ISBN 0-8493-0487-3.
  3. ↑ "mp-18748: Co3O4 (cubic, Fd-3m, 227)". materialsproject.org. Retrieved 2019-12-20.
  4. 1 2 Vilakazi, B. M.; Wagener, J. B.; van der Merwe, E. M. (2020). "A thermogravimetric investigation into the synthesis of CoF3 from Co3O4". Journal of Fluorine Chemistry. 240. doi:10.1016/j.jfluchem.2020.109638.
  5. 1 2 3 4 Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 1118. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8.
  6. ↑ "Guite". mindat.org. Retrieved 2026-03-24.
  7. ↑ Kwasnik, W. (1963). "4. Fluorine Compounds - Potassium Fluoroborate". In Brauer, Georg (ed.). Handbook of Preparative Inorganic Chemistry. Vol. 2. Translated by Riley, Reed F. (2 ed.). New York, NY: Academic Press. p. 1520.
  8. ↑ Hamer, Frank; Hamer, Janet (2004). The Potter's Dictionary of Materials and Techniques (5. ed.). Philadelphia, Pa: University of Pennsylvania Press. p. 68. ISBN 0812238109.