Molybdenum Disulfide-Based Nanocomposites as Super Oil Nano-Additive with Enhanced Tribological and Rheological Properties

Abstract

Friction is the most important phenomenon that emerges in the movement of two adjacent surfaces. The resulting wear and release of thermal energy causes failures of engines. It leads to a decrease in the performance of the mechanical system and energy loss. Among the effective ways to control these problems, lubrication is particularly important. Nowadays, adding nano-additives such as pure metals, metal oxides, metal sulfides, and carbon allotropes improves the tribological properties of lubricants. In fact, due to their potential for emission reduction and improving fuel economy, they are widely used as lubricant additives. Among nano-additives, molybdenum disulfide (MoS₂) is extensively applied as a lubricant additive due to its unique properties. But what is very important is the high dispersibility of the nano-additive in the base oil, which directly affects the tribological properties of oils. Therefore, more favorable results can be expected by overcoming the tendency to accumulate MoS₂. So, we synthesized carbon-based nanocomposites (NCs) of MoS₂ to spread on a suitable substrate, thus preventing their accumulation and using the synergistic effect of carbon materials in lubrication. MoS₂ was synthesized through two different methods, providing non-identical morphologies for MoS₂. Using the one-step hydrothermal method, we grew nanoflowers-like MoS₂ (NFLs-MoS₂) on a carbon substrate. MoS₂ with nanosheet morphology (NSs-MoS₂) was synthesized using the hydrothermal method and then spreads on carbon substrate by calcination. The tribological properties of synthesized NCs are much better than pure MoS₂ and carbon bases.