Application of graphene with excellent dispersion stability and interfacial adsorption properties under high-frequency and high-speed conditions

The lubrication performance of graphene is reduced at high frequencies and speeds owing to the agglomeration and poor interfacial adsorption of graphene. In this study, we used a mild oxidation method to prepare graphene oxide, onto which polar nitrogen-containing groups were grafted to prepare covalently modified graphene. The modified graphene retained a graphene structure and exhibited excellent dispersion stability and interfacial adsorption properties. It was stably dispersed in 500 N base oil for more than 60 days. Tribological tests with a steel ball–steel plate friction system (rate: 75 mm/s; reciprocating frequency: 25 Hz) showed that the friction coefficient of the sliding surface was ~ 0.063 when using 500 N base oil with the modified graphene as a lubricating additive, which was approximately 47.1% lower than that when using pure 500 N base oil. Graphical abstract Schematic of antifriction mechanism of MG as 500N base oil additive.