Sliding friction of graphene/hexagonal -boron nitride heterojunctions: a route to robust superlubricity.

ABSTRACT: The origin of ultra-low friction exhibited by heterogeneous junctions of graphene and hexagonal boron nitride (h-BN) is revealed. For aligned interfaces, we identify a characteristic contact size, below which the junction behaves like its homogeneous counterparts with friction forces that grow linearly with the contact area. Superlubricity sets in due to the progressive appearance of Moiré patterns resulting in a collective stick-slip motion of the elevated super-structure ridges that turns into smooth soliton-like gliding with increasing contact size. Incommensurability effects are enhanced in misaligned contacts, where the friction coefficients further drop by orders of magnitude. Our fully atomistic simulations show that the superlubric regime in graphene/h-BN heterostructures persists

SUBMITTER: Mandelli D 

PROVIDER: S-EPMC5589749 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature