Acquisition of Ultra-low Friction by a 2D Heterogeneous Interface at a High Temperature

Achieving robust lubrication across extreme temperature ranges remains a fundamental challenge in tribology. Here, we report a MoS2/Ti/Ag nano-doped film, fabricated via scalable magnetron sputtering, that exhibits self-adaptive ultra-low friction from ambient conditions to 450 °C. We distinguish the governing mechanisms at homogeneous (self-mated) and heterogeneous (paired with hydrogenated amorphous carbon (a-C:H)) interfaces, respectively. While room-temperature superlubricity in self-mated pairs arises from the shear-induced alignment of long-range ordered planes but degrades under thermal stress, the heterogeneous interface maintains an ultra-low friction coefficient of 0.02–0.04 throughout the entire temperature spectrum. At elevated temperatures, we reveal a possible dynamic reconstruction process: graphitization of the a-C:H transfer film driven by localized sp2-C clustering synergizes with Ag migration to restructure the contact area. This friction-activated mechanism may entrap carbon fragments and liberate MoS2, prompting its spontaneous re-alignment into an ordered, low-friction configuration. These findings uncover a thermally resilient, self-adaptive lubrication strategy with broad implications for aerospace and industrial applications.