Molybdenum OxySulfides tribology and Environment – MoOSE

Reducing friction in severe tribological contacts is a major concern nowadays due to the societal context of energy saving. MoS2 is a 2D material interesting to reduce friction in such contacts, whether obtained as coatings and then tested under dry conditions, or obtained by tribochemical reactions from additive molecules under severe lubricated conditions. The friction coefficients found in literature for such systems tested under open air are rarely less than 0.03, while it is possible, under ultra-high vacuum with almost pure MoS2 coating, to reach values around 0.001. Why such a difference? The environment here plays a key role on both the formation of MoS2 sheets and on their friction behavior once the sheets are formed. This project will be focused on an in-depth study of these effects still not well understood using an original scientific strategy based on a coupling of unique and specific experimental and numerical tools. A multidisciplinary consortium gathering Chemists, Physicists and Engineers and a precise control of samples is proposed to conduct this project. The main outlook of the project clearly relates to a drastic reduction of energy losses in severe tribological contacts.