Superdispersed spherical fullerenol and lamellar graphene oxide synergize to enhance the antiwear properties of water-based lubricants: Mathematical model and mechanism investigation

Abstract

The development of high-performance water-based lubricating additives with excellent properties has been the focus of research recently. Herein, carbon-based nanomaterials made of spherical fullerenol and lamellar graphene oxide (GO) were explored as water-based lubricating additives to enhance tribological properties via the response surface method systematically. The antiwear mechanisms of the carbon-based nanomaterials were revealed through simultaneous wear surface characterizations and molecular dynamics simulations. Results showed that the spherical fullerenol and lamellar GO had superdispersion stability in the water-based lubricants. Fullerenol and GO could play a superior synergistic role to considerably enhance the antiwear properties of the water-based lubricants. Particularly, the wear rate decreased by almost 93 % when the water-based lubricant was supplemented with fullerenol and GO (0.1 wt% each) at the load of 1.5 N and sliding speed of 30 mm/s. The antiwear mechanisms indicated that an excellent antiwear effect was produced by the stable tribofilms containing GO and fullerenol, which combined with hydration layers synergistically exerting a bearing capacity.