Delineating the role of ripples on thermal expansion of honeycomb materials:graphene, 2D-h-BN and monolayer(ML)-MoS2

Abstract

We delineated the role of thermally excited ripples on thermal expansion properties of 2D honeycomb materials (free-standing graphene, 2D h-BN, and ML-MoS2), by explicitly carrying out three-dimensional (3D) and two-dimensional (2D) molecular dynamics simulations. In 3D simulations, the in-plane lattice parameter (a-lattice) of graphene and 2D h-BN shows thermal contraction over a wide range of temperatures and exhibits a strong system size dependence. The 2D simulations of the very same system show a reverse trend, where the a-lattice is expanding in the whole computed temperature range. Contrary to graphene and 2D h-BN, the a-lattice of ML-MoS2 shows thermal expansion in both 2D and 3D simulations and their system size dependence is marginal. By analyzing the phonon dispersion at 300 K, we found that the discrepancy between 2D and 3D simulations of graphene and 2D h-BN is due to the absence of out-of-plane bending mode (ZA) in 2D simulations, which is responsible for thermal contraction of a-lattice at low temperature. Meanwhile, all the phonon modes are present in 2D phonon dispersion of ML-MoS2, which indicates that the origin of ZA mode is not purely due to out-of-plane movement of atoms and also its effect on thermal expansion is not significant as found in graphene and 2D h-BN

References in corpus (17)

• The electronic properties of graphene
• Van der Waals heterostructures
• Thermal Properties of Graphene, Carbon Nanotubes and Nanostructured Carbon Materials
• The structure of suspended graphene sheets
• Control of graphene's properties by reversible hydrogenation
• Intrinsic ripples in graphene
• Phonons in single and few-layer MoS2 and WS2
• Ripple Texturing of Suspended Graphene Atomic Membranes
• High-accuracy first-principles determination of the structural, vibrational and thermodynamical properties of diamond, graphite, and derivatives
• Negative Thermal Expansion Coefficient of Graphene Measured by Raman Spectroscopy
• Lattice Vibrational Modes and Phonon Thermal Conductivity of Monolayer MoS2
• Finite temperature lattice properties of graphene beyond the quasiharmonic approximation
• Probing thermal expansion of graphene and modal dispersion at low-temperature using graphene NEMS resonators
• Melting temperature of graphene
• Thermal expansion in carbon nanotubes and graphene: nonequilibrium Green's function approach
• Phonons of graphene and graphitic materials derived from the empirical potential LCBOPII
• Rippling, buckling and melting of single- and multi-layer MoS${}_2$

Cited by in corpus (3)

• Misfit strain effect on the thermal expansion coefficient of graphene/MoS${}_2$ van der Waals heterostructures
• Thermodynamic stability and vibrational anharmonicity of black phosphorene-beyond quasi-harmonic analysis
• Study of Thermal Expansion Coefficients of 2D Materials via Raman Micro-spectroscopy: Revisited