The high-speed sliding friction of graphene and novel routes to persistent superlubricity.
Recent experiments on microscopic graphite mesas demonstrate reproducible high-speed microscale superlubricity, even under ambient conditions. Here, we explore the same phenomenon on the nanoscale, by studying a graphene flake sliding on a graphite substrate, using molecular dynamics. We show that superlubricity is punctuated by high-friction transients as the flake rotates through successive crystallographic alignments with the substrate. Further, we introduce two novel routes to suppress frictional scattering and achieve persistent superlubricity. We use graphitic nanoribbons to eliminate frictional scattering by constraining the flake rotation, an approach we call frictional waveguides. We can also effectively suppress frictional scattering by biaxial stretching of the graphitic substrate. These new routes to persistent superlubricity at the nanoscale may guide the design of ultra-low dissipation nanomechanical devices.
1] International Center for Applied Mechanics, SV Lab, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, China [2] Centre for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China.
Yilun
Y
Liu
1] Centre for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China [2] Department of Physics, Tsinghua University, Beijing 100084, China [3] London Centre for Nanotechnology, University College London, London WC1H OAH, U.K [4] Centre Universitaire d'Informatique, University of Geneva, CH-1227 Carouge, Switzerland.
François
F
Grey
1] Centre for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China [2] Department of Engineering Mechanics, Applied Mechanics Lab, and State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
Quanshui
Q
Zheng