Formation of intermittent covalent bonds at high contact pressure limits superlow friction on epitaxial graphene
- Epitaxial graphene on SiC(0001) exhibits superlow friction due to its weak out-of-plane interactions. Friction-force microscopy with silicon tips shows an abrupt increase of friction by one order of magnitude above a threshold normal force. Density-functional tight-binding simulations suggest that this wearless high-friction regime involves an intermittent sp3 rehybridization of graphene at contact pressure exceeding 10 GPa. The simultaneous formation of covalent bonds with the tip's silica surface and the underlying SiC interface layer establishes a third mechanism limiting the superlow friction on epitaxial graphene, in addition to dissipation in elastic instabilities and in wear processes.
Document Type: | Article |
---|---|
Author: | Bartosz H. SzczefanowiczORCiD, Takuya KuwaharaORCiD, Tobin FilleterORCiD, Andreas KlemenzORCiD, Leonhard MayrhoferORCiD, Roland BennewitzORCiD, Michael MoselerORCiD |
URN: | urn:nbn:de:bsz:291:415-5740 |
DOI: | https://doi.org/10.1103/PhysRevResearch.5.L012049 |
Parent Title (English): | Physical Review Research |
Volume: | 5 |
Issue: | 1 |
First Page: | L012049 |
Language: | English |
Year of first Publication: | 2023 |
Release Date: | 2023/04/14 |
Tag: | adhesion; chemical bonding; friction; lubrication; pressure effects |
Impact: | 03.900 (2021) |
Scientific Units: | Interactive Surfaces |
DDC classes: | 500 Naturwissenschaften und Mathematik / 530 Physik |
Open Access: | Open Access |
Signature: | INM 2023/049 |
Licence (German): | Creative Commons - CC BY - Namensnennung 4.0 International |