Speaker
Description
Efficient lubrication is essential to reduce energy losses, minimise wear, and extend the lifetime of mechanical components. Solid lubricants, particularly layered two-dimensional (2D) materials, have attracted significant attention due to their low shear strength and unique interfacial properties. However, practical implementation remains challenging, as particulate lubricants exhibit poor adhesion to substrates and are rapidly removed from the contact interface during operation.
Among 2D materials, MXenes such as $Ti_3C_2T_x$ offer promising tribological performance but suffer from environmental instability, particularly hydrolysis under ambient conditions.[1,2] To address both adhesion and stability limitations, we systematically developed composite lubricating coatings by combining 2D materials with organic polymer matrices.
Layered materials, $Ti_3C_2T_x$, $MoS_2$, and graphite, were dispersed with fluorine-free polymers such as PMMA, PLA, PS, PIP, and PVDF via ultrasonic solution blending to form inks. These inks were deposited onto substrates using airbrushing and electrospraying techniques, yielding uniform coatings with significantly improved adhesion compared to pure powder films. Tribological testing reveals that polymer incorporation enables persistent lubrication by preventing lubricant loss from the interface. Soft polymer matrices provide moderate but stable friction reduction over extended sliding durations, whereas harder polymers exhibit initially low friction coefficients but undergo rapid removal, limiting long-term performance. Notably, certain polymer systems partially suppress MXene degradation, enhancing environmental stability.
Despite these advantages, the exceptional lubricating properties of MXenes in powder form are not fully retained in the composite coatings, which underperform relative to polymer-free references.[3] This highlights the critical role of interfacial structure and matrix interactions in governing tribological behaviour. These findings demonstrate that while polymer-2D material composites offer a viable pathway toward durable solid lubrication, optimising matrix-filler interactions remains essential to fully exploit the potential of advanced 2D materials in tribological applications.
[1] Huang, S. & Mochalin, V. N. Hydrolysis of 2D Transition-Metal Carbides (MXenes) in Colloidal Solutions. Inorganic Chemistry 58, 1958–1966 (2019)
[2] Göçerler, H. et al. Unlocking the synergistic impact of laser texturing and Ti3C2Tx MXene coatings – Substrate-specific tribological insights. Carbon 238, 120270 (2025).
[3] Rosenkranz, A., Righi, M. C., Sumant, A. V., Anasori, B. & Mochalin, V. N. Perspectives of 2D MXene Tribology. Advanced Materials 35, 2207757 (2023)