Abstract

This study demonstrated the successful synthesis of UiO-66-NH2 through a solvothermal reaction employing zirconium chloride (ZrCl4) and 2-aminoterephthalic acid (NH2BDC) as metal cluster precursors and organic linkers, respectively. The synthesized UiO-66-NH2 was subsequently employed to encapsulate gallium-based liquid metal (GLM) nanoparticles via an in-situ confinement strategy, leading to the development of a novel heterogeneous nanocomposite material (designated as MOF@GLM-NPs). When incorporated as a water-based lubricant additive, the MOF@GLM-NPs composite demonstrated exceptional tribological performance, achieving significant reductions in both the friction coefficient (54.2 %) and wear rate (50.8 %) compared to the base water for AISI E52100 steel disc counterparts at optimal additive concentration (0.6 wt%). The superior tribological performance is attributed to the nanocomposite's high dispersibility and colloidal stability in water, which facilitates the gradual migration of active components to the friction interface, enabling the formation of a continuous protective tribofilm enriched with gallium-based species. These findings advance the understanding of liquid metal-based nanocomposite design and provide valuable insights for developing high-performance lubricant additives through rational material hybridization strategies.

Keywords Plus: GLOBAL ENERGY-CONSUMPTION，ORGANIC FRAMEWORK，FRICTION

Published in APPLIED SURFACE SCIENCE，Volume741；10.1016/j.apsusc.2026.167095，SEP 30 2026