Heterostructured Ti ₃ C ₂ T _x /Mo-CDs/NiCo-MOF Nanoadditives for Oil Lubricants

This study presents the construction of an alternatingly layered 2D/0D/2D heterostructured composite comprising MXene, zero-dimensional carbon dots (CDs), and metal–organic frameworks (MOFs). The composite was synthesized through the ordered integration of these components using a hydrothermal method enhanced by electrostatic attraction. The resulting nanoadditive was then dispersed in the base oil PAO6 to assess its dispersion stability and tribological performance. Results: The composite nanoadditive exhibited superior dispersion stability. When subjected to a normal load of 40 N at room temperature, PAO6 containing 0.1 wt % MXene/CDs/MOF demonstrated a significantly lower friction coefficient and reduced wear volume compared to the base oil, with decreases of 18.3% and 48.2%, respectively. This exceptional lubricating performance arises from the synergistic effects of the three components: MXene provides outstanding wear resistance and load-bearing capacity; MOFs, benefiting from the interlayer sliding effect of their bimetallic skeleton, contribute to stable lubrication; and ultrafine CDs rapidly fill wear scars, facilitating a self-repairing function. The synergy among the three components enables the composite to achieve rapid response and self-adaptation under varying operating conditions, demonstrating excellent adaptability across multiple working conditions. This material presents significant application potential in areas such as high-load mechanical transmission, aerospace bearings, and high-temperature engines, offering insights for the broader utilization of composites in tribology.