Abstract

Multilayer Ti3C2TX nanosheets (MXenes) have gained notable attention in the tribological community due to their outstanding wear resistance induced by their ability to form beneficial tribolayers. Regarding delaminated, few-layer Ti3C2Tx nanosheets, much less knowledge about their tribological performance is available. Therefore, this study aims at comparing the solid lubrication ability of spray-coated few- or multilayer Ti3C2Tx coatings (dispersion concentrations of 2 and 5 mg mL(-1)). Linear-reciprocating ball-on-disk tests are conducted using normal loads of 100 and 200 mN. The results clearly demonstrate the superior tribological performance of multilayer Ti3C2Tx nanosheets, inducing a low, stable, and reproducible evolution of the coefficient of friction. This holds particularly true for coatings fabricated with the lower concentrated dispersion, which are characterized by a reduced coating thickness and less lubricious material. In contrast, few-layer MXenes, irrespective of the coating thickness and available amount of lubricious material (dispersion concentration), demonstrate continuously rising frictional values, which can be traced back to the nanosheets' degradation.