Effect of strain on atomic-scale friction in layered MoS2

• The atomic-scale friction in MoS2 is investigated by the density functional theory.
• The in-plane compressive MoS2 exhibits lower friction than the tensile system.
• The reduced friction is attributed to the charge transfer to the sliding interface.
• The friction can be tuned by applying an in-plane strain to the sliding interface.

The atomic-scale friction in MoS2 is investigated employing the density functional theory calculation including the dispersion correction (DFT-D). Energy corrugations and lateral frictional forces of the lamellar MoS2 are derived, suggesting that the in-plane compressive MoS2 exhibits lower friction than the tensile system. The reduced friction is attributed to a stronger coulombic repulsive interaction enabled by the transferred charge to the sliding interface. In-depth understanding of the relationship between friction and interfacial interaction shows that friction can be tuned in layered MoS2 by applying an in-plane strain to the sliding interface.

The energy corrugation (a) and the maximum lateral frictional force (b) for different in-plane strains as a function of the normal force.Figure optionsDownload high-quality image (243 K)Download as PowerPoint slide