Reinforcement of tribological performance assisted by in-situ carbon layer from the release, capture and tribo-chemistry of ionic liquid hydrotalcite composite lubricating materials

The tribofilm is crucial for the improvement of tribological properties, and the modulation of interfacial tribofilm through system construction and component optimization has become an important strategy to obtain excellent lubrication stability. In this work, ionic liquid (IL) functionalized hydrotalcite composites (IL-LDH) were designed and prepared as lubricating additives. The hydrotalcite was successfully exfoliated by ILs, and obtained a thinner and more flexible lamellar morphology structure. Meanwhile, the composite additives significantly improve the friction reduction, anti-wear and load-bearing properties of the basic system. The significantly improved tribological properties by IL-LDH are attributable not only to the formation of in-situ carbon layer contributed by the release and capture of ILs between the composite layers under shear, but also to the friction-induced organic-inorganic doped tribofilm under the coupling of multiple effects.