Unveiling How Atomic Defects and Force Fields Influence Friction in 2D MoS2 Surfaces

ABSTRACT Two‐dimensional molybdenum disulfide (MoS) has emerged as a promising material for desalination and nanofluidic applications due to its unique interfacial properties. However, the impact of defects, such as vacancies and atomic steps, on water interaction and flow behavior is still not well understood. An accurate estimate of water flow behavior on solid surfaces requires understanding the complex solid–liquid interactions that govern liquid transport at the molecular level. Molecular simulations can provide key insights into the spatial and temporal behavior of solid–liquid interfaces. But, such insights depend on the ability of force fields to describe the underlying phenomena. In this work, combined density functional theory and molecular dynamics simulations were used to investigate the effect of defects and force field parameters on the frictional coefficient and water slip length (WSL) in MoS surfaces. We utilized two distinct force fields to represent the MoS material. Our findings reveal that the frictional coefficient and the WSL are significantly affected by atomic defects and force field parameters. Surprisingly, we find that while the frictional coefficient and WSL values exhibit substantial variation depending on the type of atomic defects, they remain consistent for two force fields when applied to the armchair and zigzag edges.