Molybdenum ditelluride
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| Names | |
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IUPAC name
bis(tellanylidene)molybdenum
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| Other names
molybdenum(IV) telluride
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| Identifiers | |
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3D model (JSmol)
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| ChemSpider | |
| ECHA InfoCard | 100.031.832 |
| EC Number | 235-028-4 |
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PubChem CID
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| Properties | |
| MoTe 2 |
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| Molar mass | 351.14 g/mol |
| Appearance | black/lead-gray solid |
| Density | 7.7 g/cm3 |
| Melting point | decomposes |
| insoluble | |
| Solubility | decomposed by nitric acid insoluble in non-oxidising acids |
| Band gap | 1.1 eV (direct, monolayer) 0.9 eV (indirect, bulk) |
| Structure | |
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hP6, P63/mmc, No. 194 (α or 2H) |
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| Related compounds | |
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Other anions
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molybdenum(IV) oxide molybdenum disulfide molybdenum diselenide |
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Other cations
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tungsten ditelluride |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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 (what is   ?) |
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| Infobox references | |
Molybdenum(IV) telluride, molybdenum ditelluride or just molybdenum telluride is a compound of molybdenum and tellurium with formula MoTe2, corresponding to a mass percentage of 27.32% molybdenum and 72.68% tellurium. It can crystallise in two dimensional sheets which can be thinned down to monolayers that are flexible and almost transparent. It is a semiconductor, and can fluoresce. It is part of a class of materials called transition metal dichalcogenides. As a semiconductor the band gap lies in the infrared region. This raises the potential use as a semiconductor in electronics or an infrared detector.
MoTe2 can be prepared by heating the correct ratio of the elements together at 1100 °C in a vacuum. Another method is via vapour deposition, where molybdenum and tellurium are volatilised in bromine gas and then deposited. Using bromine results in forming an n-type semiconductor, whereas using tellurium only results in a p-type semiconductor.
The amount of tellurium in molybdenum ditelluride can vary, with tellurium being slightly deficient unless it is added in excess during production. Tellurium molecular proportion range from 1.97 to 2. Excess tellurium deposited during this process can be dissolved off with sulfuric acid.
By annealing molybdenum film in a tellurium vapour at 850 to 870 °C for several hours, a thin layer of MoTe2 is formed.
An amorphous form can be produced by sonochemically reacting molybdenum hexacarbonyl with tellurium dissolved in decalin.
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