Mechanical and thermal properties of h-MX{sub 2} (M = Cr, Mo, W; X = O, S, Se, Te) monolayers: A comparative study

Journal Article · Mon May 19 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4879543· OSTI ID:22300182

Çakır, Deniz; Sevik, Cem ^[1]

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1. Department of Mechanical Engineering, Faculty of Engineering, Anadolu University, Eskisehir TR 26555 (Turkey)

Using density functional theory, we obtain the mechanical and thermal properties of MX{sub 2} monolayers (where M = Cr, Mo, W and X = O, S, Se, Te). The Γ-centered phonon frequencies (i.e., A{sub 1}, A{sub 2}{sup ″}, E′, and E″), relative frequency values of A{sub 1}, and E′ modes, and mechanical properties (i.e., elastic constants, Young modulus, and Poisson's ratio) display a strong dependence on the type of metal and chalcogenide atoms. In each chalcogenide (metal) group, transition-metal dichalcogenides (TMDCs) with W (O) atom are found to be much stiffer. Consistent with their stability, the thermal expansion of lattice constants for TMDCs with O (Te) is much slower (faster). Furthermore, in a heterostructure of these materials, the difference of the thermal expansion of lattice constants between the individual components becomes quite tiny over the whole temperature range. The calculated mechanical and thermal properties show that TMDCs are promising materials for heterostructures.

• OSTI ID: 22300182
• Journal Information: Applied Physics Letters, Vol. 104, Issue 20; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ATOMS
CHALCOGENIDES
CHROMIUM COMPOUNDS
COMPUTERIZED SIMULATION
DENSITY FUNCTIONAL METHOD
LATTICE PARAMETERS
LAYERS
MECHANICAL PROPERTIES
MOLYBDENUM COMPOUNDS
OXIDES
SELENIDES
STABILITY
SULFIDES
TELLURIDES
THERMAL EXPANSION
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN COMPOUNDS
YOUNG MODULUS