Lubricating properties of molybdenum disulphur: a density functional theory study

The lubrication properties of MoS2 have been described in terms of electronic interactions between MoS2 sheets calculated through slab periodic density functional calculations. This approach is supported by experimental works on the ultrahigh vacuum friction of MoS2 coatings of thicknesses in the micrometer range (Phys. Rev. 48 (14) (1993) 10583), and in boundary lubrication by molybdenum containing organic compounds, such as molybdenum dithiocarbamate (J. Vac. Sci. Technol. A 17 (1999) 884). In this latter case we have shown that the friction reducing effect is ensured by in situ formed MoS2 single sheets.