NCAFM2023 Programme Booklet

FRICTION FORCE MICROSCOPY OF GRAPHENE ON A PLATINUM SURFACE

Th. Glatzel 1 , Z. Liu1, 2 , J.G. Vilhena 3 , A. Hinaut 1 , S. Scherb 1,4 , F. Luo 2 , J. Zhang 5 , E. Gnecco 6 , and E. Meyer 1

1 University of Basel, Dep. of Physics, Klingelbergstr. 82, 4056 Basel, Switzerland 2 Nankai University, School of Materials Science and Engineering, 300350 Tianjin, China 3 Universidad Autónoma de Madrid, Dep. of Theoretical Condensed Matter Physics, 28049 Madrid, Spain 4 Institute for Molecules and Materials, Radboud University, 6525 AJ Nijmegen, Netherlands 5 State Key Laboratory of Solid Lubrication, Chinese Academy of Sciences, 730000 Lanzhou, China 6 M. Smoluchowksi Institute of Physics, Jagiellonian University in Krakow, 30-348 Krakow, Poland

Email: thilo.glatzel@unibas.ch

Friction control and technological advancement are deeply connected. Two dimensional materials play a significant role in achieving near-frictionless contacts. However, there is a challenge in adjusting the sliding of superlubric materials. Taking inspiration from twistronics, we studied the control of superlubricity through moiré patterning [1,2]. Through friction force microscopy and molecular dynamics simulations, we demonstrated that different twist angles of graphene moirés on a Pt(111) surface lead to a transition from superlubric to dissipative sliding regimes under various normal forces. This is due to a new mechanism at the superlattice level, where moiré tiles undergo a highly dissipative shear process connected to the twist angle beyond a critical load. Importantly, the atomic-level dissipation associated with moiré tile manipulation allows bridging different sliding regimes in a reversible manner, offering a way to subtly control superlubricity.

Fig. 1 : Surface structure and frictional response of graphene on Pt(111): (a) Torsional frequency shift ∆ft measured in nc-AFM of four twist configurations. Scale bars: 2nm. (b) Corresponding average friction force as a function of the normal force. References [1] Z. Liu, J.G. Vilhena, A. Hinaut, S. Scherb, F. Luo, J. Zhang, Th. Glatzel, E. Gnecco, and E. Meyer, Nano Letters, https://doi.org/10.1021/acs.nanolett.2c03818, 2023. [2] Y. Song, X. Gao, A. Hinaut, S. Scherb, S. Huang, Th. Glatzel, O. Hod, M. Urbakh, and E. Meyer, Nano Letters, https://doi.org/10.1021/acs.nanolett.2c03667, 2022, 22 , 9529-9536.

119