Molecular dynamics study on the mechanical properties of multilayer MoS2 under different potentials

Nanotechnology. 2020 May 22;31(21):215703. doi: 10.1088/1361-6528/ab73b3. Epub 2020 Feb 7.

Abstract

Experiments and simulations have shown that molybdenum disulfide (MoS2) has unique mechanical and electrical properties that make it promising for application as a flexible material in microscopic and nanoscopic electronic devices. In this paper, the molecular dynamics method is used to study the mechanical properties of multilayer MoS2 during compression and stretching under different intra-layer and inter-layer potentials to choose the most suitable ones. The results show that the increase in the inter-layer repulsive force during compression was all provided by sulfur atoms in the adjacent layer. The two intra-layer potentials represented two forms of tensile fracture: plastic fracture with structural holes or lattice distortions, and brittle fracture with instantaneous destruction. The chosen inter-layer potential had a significant influence on the structure of the multilayer MoS2 but the effect of inter-layer potential during stretching was not prominent. By comparing these results with reference values, the most suitable intra-layer and inter-layer potentials for the multilayer MoS2 were selected, and can serve as a reliable reference for subsequent simulations.