▎ 摘　　要

We report for the first time that nanosized MoS2 on graphene (MoS2/Gr) was used as an additive in perfluoropolyether (PFPE) base oil. The nanocomposite can not only form a stable dispersion in PFPE for two weeks but also dramatically improve the friction-reduction and anti-wear properties of the base oil for steel/steel contact under high vacuum.