Cobalt(II) selenide
From Wikipedia, the free encyclopedia
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| Names | |
|---|---|
| IUPAC name
Cobalt(II) selenide | |
| Identifiers | |
3D model (JSmol) |
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| ECHA InfoCard | 100.013.778 |
| EC Number |
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PubChem CID |
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CompTox Dashboard (EPA) |
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| Properties | |
| CoSe | |
| Molar mass | 137.89 g/mol[1] |
| Density | 7.65 g/cm3[1] |
| Melting point | 1,055 °C (1,931 °F; 1,328 K)[1] |
| Insoluble[1] | |
| Structure[2] | |
| Hexagonal (NiAs), hP4 | |
| P63/mmc, No. 194 | |
a = 0.362 nm, b = 0.362 nm, c = 0.52 nm α = 90°, β = 90°, γ = 120° | |
Formula units (Z) |
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| Hazards | |
| GHS labelling:[3] | |
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| Danger | |
| H301, H331, H373, H410 | |
| P260, P264, P270, P271, P273, P301+P316, P304+P340, P316, P319, P321, P330, P391, P403+P233, P405, P501 | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Cobalt(II) selenide is an inorganic compound with the chemical formula CoSe. The mineral form of this compound is known as freboldite.[4] Similar minerals include trogtalite (CoSe2)[5] and bornhardtite (Co2+Co3+2Se4).[6]
Cobalt(II) selenide can be prepared by placing cobalt selenite in 10% sodium hydroxide solution, stirring it, and adding it drop by drop into the 10% sodium hydroxide solution of sodium thiosulfate. When the color of the reaction solution no longer changes, let it stand, filter, and use water and wash it with 5% hydrochloric acid and dry it to obtain CoSe.[7]
Cobalt(II) selenide can also be produced by the electrodeposition reaction of cobalt(II) acetate and sodium selenite in acidic solution. When the pH is 3.5, the ratio of cobalt and selenium in the compound is closest to 1:1; too low a pH will make the compound rich in selenium, while higher The pH will be rich in cobalt.[8]