Persistence of Structural Lubricity on Contaminated Graphite: Rejuvenation, Aging, and Friction Switches.

ABSTRACT: Using atomic force microscopy experiments and molecular dynamics simulations of gold nanoislands on graphite, we investigate why ultralow friction commonly associated with structural lubricity can be observed even under ambient conditions. Measurements conducted within a few days after sample synthesis reveal previously undiscovered phenomena in structurally lubric systems: rejuvenation, a drop in kinetic friction of an order of magnitude shortly after the onset of sliding; aging, a significant increase in kinetic friction forces after a rest period of 30 min or more; and switches, spontaneous jumps between distinct friction branches. These three effects are drastically suppressed a few weeks later. Imaging of a contamination layer and simulations provide a consistent

SUBMITTER: Oo WH 

PROVIDER: S-EPMC11450813 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature