Fig. 1: Friction measurement of superlubric graphite flake and two types of silicon surfaces.
From: Robust microscale structural superlubricity between graphite and nanostructured surface
a Schematic diagram of the experimental setup to measure the friction of graphite/silicon interface. The silicon substrate was rigidly fixed to the piezoelectric ceramic transducer (PZT) stage on top of which an Au capped graphite flake was placed. Normal force and lateral force are applied by pressing the AFM tip on the top of the Au cap. When the PZT stage reciprocates with velocity \(v\), the AFM tip will drag the graphite flake to relative slide on the silicon substrate. b Optical microscopic image of experimental set-up. c and e are the surface topography of atomic-level smooth surface and nanostructured surface, respectively. d, f The lateral force signal when graphite flake sliding on the atomic-level smooth surface and nanostructured surface respectively, with a displacement amplitude of \(1\,{{{{{\rm{\mu }}}}}}{{{{{\rm{m}}}}}}\) and a speed of \(2\,{{{{{\rm{\mu }}}}}}{{{{{\rm{m}}}}}}/{{{{{\rm{s}}}}}}\) under a normal force of 20.04 \({{{{{\rm{\mu }}}}}}{{{{{\rm{N}}}}}}\). Source data are provided as a Source Data file.
