Abstract

Transition metal diselenides, like the commonly used space lubricant material MoS2, exhibit significant potential in the field of solid lubrication due to their layered structure and low shear strength. In this work, we employed High-Power Impulse Magnetron Sputtering (HiPIMS) to deposit NbSe2, MoSe2, and WSe2 thin films, systematically investigating their film-forming characteristics, mechanical properties, and tribological responses in different environments (ambient atmosphere, high vacuum, and simulated CO2-rich Martian low-pressure atmosphere). Experimental results indicate that all three films possess a dense microstructure, with a hardness of no less than 2.9 GPa and an elastic modulus exceeding 53 GPa. Tribological tests reveal a significant influence of the atmospheric environment on film performance. In the simulated CO2-rich Martian environment, the friction coefficients of transition metal diselenide films decreased markedly compared to those under vacuum. Especially, WSe2 films achieving an ultralow friction coefficient of 0.014 under a 10 N load, with significantly decreased wear rates (0.39 & times; 10-7 mm3 center dot N-1 center dot m-1). First-principles calculation, TEM and XPS analyses reveal that CO2 facilitates the formation of a more ordered and lamellar interfacial lubricating layer and enhances the continuity of transfer films, NbSe2 forms a niobium-rich transition layer that strengthens transfer film adhesion specifically, which are key mechanisms governing the friction coefficient and wear behavior.

Keywords Plus: LOW FRICTION，THIN-FILMS，MOS2，BEHAVIOR，NANOPARTICLES，WS2

Published in TRIBOLOGY INTERNATIONAL，Volume219；10.1016/j.triboint.2026.111829，JUL 2026