MoS2/reduced graphene oxide hybrid structure and its tribological properties

Abstract

In this study, a MoS₂/reduced graphene oxide hybrid material (MoS₂/RGO) was synthesized through a facile and effective hydrothermal method. Fe–Ni matrix composites with different weight fractions of MoS₂/RGO were prepared by a powder metallurgy (P/M) technique (1%, 3%, 5%, 7%), and their tribological properties at temperatures ranging from room temperature to 600 °C were investigated using a UMT-2 ball-on-plate friction and wear tester. Results showed that MoS₂ nanospheres composed of many petal-like nanosheets were well attached to the creased RGO sheets. The Fe–Ni matrix composites with suitable MoS₂/RGO content exhibited excellent friction-reducing and anti-wear properties over a wide temperature range, and the RGO in the MoS₂/RGO hybrid material played an important role in the hardness and tribological performance of composites. In particular, the specimen with 3 wt% MoS₂/RGO showed the lowest friction coefficient (0.21) and the most stable value of wear rate (1.07–1.90 × 10⁻⁵ mm³ N⁻¹ m⁻¹). And at 600 °C, the friction coefficient was less than 0.30 and the wear rate was 1.07 × 10⁻⁵ mm³ N⁻¹ m⁻¹ due to the lubricating effect of sulfide films and glaze layer formed on the friction surface at high temperature. The excellent tribological behavior of composites was attributed to the synergetic effect of high hardness and solid lubricants.