Friction and atomic-layer-scale wear of graphitic lubricants on SiC(0001) in dry sliding

Microscale study of frictional properties of graphene in ultra high vacuum

“…The RMS roughness of the spheres was previously measured to be 11 nm on a scale of 5 μm leading to a multiple asperities contact as confirmed by Wählisch et al [25].…”

Wear properties of graphene edges probed by atomic force microscopy based lateral manipulation

“…Therefore, graphene can be applied as an extremely compact protective coating for friction and wear reduction [2,4,5,6,7,8], as an anti-corrosion layer [9], for van der Waals screening [10], as a lubricant for rotating and sliding electrical contacts [11], for the mechanical encapsulation and protection of molecules and 10 cells [12,13,14,15], and for flexible optoelectronics [16,17,18,19].…”

Micro- and Nanotribology of Graphene

“…This technique has been used to demonstrate the lubrication by graphene on a number of substrates, where the friction was found to be lower on graphene patches as compared to the surrounding substrate surface. Examples include graphene patches on SiC(0001) [7], silicon oxide [8,9], and copper foils [10]. In the latter work of Marsden et al on graphene growth on copper foils, the simultaneous recording of topography and lateral force allowed for a correlation of substrate surface structure and graphene growth.…”

“…20.3 could not always be reproduced. For a better understanding Wählisch et al [7] used a similar microtribometer as in [40] and combined it with an Agilent 5400 AFM in order to investigate the wear track without transferring the substrate from the microtribometer to the AFM. Using this setup it was possible [40] to correlate the friction force with the contact area between ruby sphere and the graphene coated sample (see Fig.…”

“…The numbers indicate the order of experiments under equal conditions. From [7] friction force was caused by different contact geometries between the ruby sphere and the graphene sample during experiments although the experimental conditions were kept identical. Moreover the authors found that the graphene layer is quickly worn in the wear track due to high contact pressures at step edges.…”