Formula Co3O4 Melting point 895 °C Boiling point 900 °C | Molar mass 240.8 g/mol Density 6.11 g/cm³ Appearance black solid | |
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Cobalt(II,III) oxide is inorganic compound with the formula Co3O4. It is one of two well characterized cobalt oxides. It is a black antiferromagnetic solid. As a mixed valence compound, its formula is sometimes written as CoIICoIII2O4 and sometimes as CoO•Co2O3.
Contents
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.
Synthesis
Cobalt(II) oxide, CoO, converts to Co3O4 if heated to around 600-700 °C in air. Above 900 °C, CoO is stable. These reaction are described by the following equilibrium:
2 Co3O4 ⇌ 6 CoO + O2Research
This inorganic compound is currently utilized in the process of artificial photosynthesis.
Safety
Cobalt compounds are potentially poisonous in large amounts.