Description
Cobalt Oxide (II, III) is a kind oxide of cobalt. It has applications in enamels, semiconductors, grinding wheels. As an important inorganic material, it can be used in catalysis, superconductors, ceramics and other fields. It can also be used as catalyst and catalyst carrier, as electrode active material, for glass, porcelain colorants and pigments, as chemical industry oxidant and as a catalyst for organic synthesis, in senior goggles and other filter materials, in temperature and gas sensors, in electronic ceramics, in lithium ion battery electrode materials, magnetic materials, electrochromic devices, enamels, solar energy absorbers. Cobalt oxide nanoparticles can readily enter cells, and have the potential to be used for hyperthermic treatment, gene therapy and drug delivery. It is more commonly applied for energy storage such as Lithium-ion battery. It may also be used as a gas sensor in sensing toluene, acetone and some other toxic vapors.
Preparation
Tricobalt tetroxide is obtained when cobalt(II) carbonate, cobalt(II) or cobalt(III) oxide, or cobalt hydroxide oxide, CoO(OH) is heated in air at temperatures above 265°C. The temperature must not exceed 800°C (see decomposition temperature above).
Reactions
Heating above 900°C expels oxygen out of the molecule forming cobalt(II) oxide:
2Co3O4 6CoO + O2
Tricobalt tetroxide absorbs oxygen at lower temperatures, but there is no change in the crystal structure.)
The oxide is reduced to its metal by hydrogen, carbon or carbon monoxide.
Co3O4 + 4H2 3Co + 4H2O
Co3O4 + 4CO 3Co + 4CO2
Sources
https://en.wikipedia.org/wiki/Cobalt(II,III)_oxide
https://www.alfa.com/zh-cn/catalog/040184/
https://en.wikipedia.org/wiki/Cobalt_oxide_nanoparticle
https://pubchem.ncbi.nlm.nih.gov/compound/6432046#section=Top
Chemical Properties
Black fine powder
Physical properties
Black cubic crystal; density 6.11 g/cm
3; decomposes above 900°C, losing oxygen; insoluble in water; soluble in acids and alkalis.
Uses
It is used in artificial photosynthesis. It is used as a magnetic semiconductor. It is also employed in supercapacitors and lithium-ion batteries.
Uses
In enamels; in semiconductors; in grinding wheels.
Flammability and Explosibility
Not classified