Synthesis of hollow fullerene-like molybdenum disulfide/reduced graphene oxide nanocomposites with excellent lubricating properties

In this paper, bubble-on-plate structure is realized on hollow IF-MoS₂/reduced graphene oxide (HIF-MoS₂/RGO) nanocomposites. HIF-MoS₂ nanocages templated with the generated ammonia (NH₃) are connected to RGO through the interlayered MoS₂. The as-prepared HIF-MoS₂/RGO is added into an ionic grease to study the tribological behavior of HIF-MoS₂/RGO. For comparison, commercial grade MoS₂ nanoparticles, single RGO or HIF-MoS₂ or their physical mixture are also studied. Tribological results show that, compared with other additives, HIF-MoS₂/RGO nanocomposites have the best anti-wear properties especially under higher load of 3.0 GPa. The wear reduction of HIF-MoS₂/RGO reinforced grease under 2.5 GPa and 3.0 GPa reached 67% and 96%, respectively. In addition, HIF-MoS₂/RGO reinforced grease achieves much lower and stable friction coefficient (0.079, the value of neat grease is 0.098) under 3.0 GPa. HIF-MoS₂/RGO reinforced grease maintains very low friction coefficient and wear up to 4.1 GPa, while the normal MoS₂ and RGO show high wear at the pressure up to 3.0 GPa. It is proposed that HIF-MoS₂ nanocages on RGO act as rolling balls during friction resulting in better separation of steels.