| Names | |
|---|---|
|  IUPAC name  Copper(I) selenide  | |
| Other names  Cuprous selenide, dicopper selenide  | |
| Identifiers | |
3D model (JSmol)  | |
| ChemSpider | |
| ECHA InfoCard | 100.039.799 | 
| EC Number | 
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 PubChem CID  | |
| UNII | |
 CompTox Dashboard (EPA)  | |
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| Properties | |
| Cu2Se | |
| Molar mass | 206.063 g·mol−1 | 
| Appearance | Dark blue, black | 
| Density | 6.84 g/mL [1] | 
| Hazards | |
| GHS labelling: | |
|   | |
| Danger | |
| H201, H331, H373, H410 | |
| P260, P261, P264, P270, P271, P273, P301+P310, P304+P340, P311, P314, 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).  | |
Copper(I) selenide is an inorganic binary compound between copper and selenium, with the chemical formula Cu2Se. [2]
Stoichiometric copper selenide is a zero-bandgap material with metal-like behavior. [3] Copper-deficient Cu2−xSe (non-stoichiometric) is an intrinsic p-type semiconductor with direct and indirect bandgap energies in the range of 2.1–2.3 eV and 1.2–1.4 eV respectively. [4] It is frequently grown as nanoparticles or other nanostructures. [5] [6] [7]
Copper(I) selenide is produced in situ to form a protective black coating on iron or steel parts in some cold-bluing processes. [8] Bluing solutions that operate in this manner will typically be labeled as containing selenous acid or selenium dioxide. [9] [10] It has also been investigated for use in the treatment of colon cancer. [6]
Copper selenides are the most common selenium minerals. Cu2Se occurs as two polymorphs: berzelianite [11] (isometric, more common) and bellidoite (tetragonal). There are more natural Cu selenides to date, including umangite, Cu3Se2 and athabascaite, Cu5Se4. [12]