Improving the lubricating properties of base oils through additives is a crucial objective of tribological research, as it helps to reduce friction and wear of materials. Molybdenum disulfide (MoS₂) is a 2D nanomaterial with excellent tribological properties that is often used as a lubricant additive. Several studies have been conducted on the preparation and utilization of MoS₂ and its nanocomposites as lubricant additives. This paper reviews the research progress on MoS₂ nanomaterials as lubricant additives. It firstly introduces various synthesis methods of MoS₂ nanomaterials while focusing on the preparation of nano-MoS₂ as lubricant additives. It then summarizes the dispersion stability of nano-MoS₂ in lubricating oils which has been paid extensive attention. Moreover, this paper reviews and discusses the tribological properties of nano-MoS₂ and its various composites as lubricant additives. The possible anti-wear and friction reduction mechanisms of nano-MoS₂ and its composites are also discussed. Finally, this paper presents the challenges faced by nano-MoS₂ additives in the field of lubrication and the prospects for future research in view of previous studies.

This study aimed to evaluate camphor tree ash (green biomass ash) supported K₂CO₃ as a solid base catalyst for biodiesel production. The catalyst was prepared by way of first-calcination, K₂CO₃ solution impregnation, and second-calcination method. The catalytic performance of the catalyst for the preparation of biodiesel was investigated. Under the optimal conditions of K₂CO₃ loading of 50 wt%, first-calcination temperature of 800°C, second-calcination temperature of 500°C, catalyst concentration of 5 wt%, catalytic time of 210 min, methanol/oil molar ratio of 14:1, and catalytic temperature of 65°C, the biodiesel yield reached 92.27%.