▎ 摘　　要

In this work, the anti-friction and anti-wear capacity of 0.05 wt% graphene or/and 0.5 wt% MoDTC were investigated in PAO base oil at different test temperatures. Sliding surfaces were analyzed by scanning electron microscope, X-ray energy dispersive spectrometer, and Raman spectroscopy. Results indicated that graphene alone as an additive mildly reduced the friction coefficient at low test temperatures due to its easy shear and ultrathin lamellar structure. MoDTC alone effectively reduced the friction coefficient at different test tempera-tures because of the formation of MoS2 tribo-film. The excellent mechanical and thermal properties of graphene tribo-film and the good lubricity of MoS2 tribo-film contributed to the enhanced anti-wear capacity of graphene and MoDTC additives, respectively. Graphene-MoDTC dual additive further improved the lubricating perfor-mance of PAO base oil. It was shown that MoS2 tribo-film derived from MoDTC dominated the friction behavior of graphene-MoDTC dual additive and graphene nanosheets further improved the anti-wear characteristics of the dual additive. It suggests that the combination of graphene and MoDTC supplies a feasible additive formulation design for PAO base oil at steel/steel interface.