TY - JOUR
T1 - Effect of Atomic Corrugation on Adhesion and Friction
T2 - A Model Study with Graphene Step Edges
AU - Chen, Zhe
AU - Vazirisereshk, Mohammad R.
AU - Khajeh, Arash
AU - Martini, Ashlie
AU - Kim, Seong H.
N1 - Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/11/7
Y1 - 2019/11/7
N2 - This Letter reports that the atomic corrugation of the surface can affect nanoscale interfacial adhesion and friction differently. Both atomic force microscopy (AFM) and molecular dynamics (MD) simulations showed that the adhesion force needed to separate a silica tip from a graphene step edge increases as the side wall of the tip approaches the step edge when the tip is on the lower terrace and decreases as the tip ascends or descends the step edge. However, the friction force measured with the same AFM tip moving across the step edge does not positively correlate with the measured adhesion, which implies that the conventional contact mechanics approach of correlating interfacial adhesion and friction could be invalid for surfaces with atomic-scale features. The chemical and physical origins for the observed discrepancy between adhesion and friction at the atomic step edge are discussed.
AB - This Letter reports that the atomic corrugation of the surface can affect nanoscale interfacial adhesion and friction differently. Both atomic force microscopy (AFM) and molecular dynamics (MD) simulations showed that the adhesion force needed to separate a silica tip from a graphene step edge increases as the side wall of the tip approaches the step edge when the tip is on the lower terrace and decreases as the tip ascends or descends the step edge. However, the friction force measured with the same AFM tip moving across the step edge does not positively correlate with the measured adhesion, which implies that the conventional contact mechanics approach of correlating interfacial adhesion and friction could be invalid for surfaces with atomic-scale features. The chemical and physical origins for the observed discrepancy between adhesion and friction at the atomic step edge are discussed.
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U2 - 10.1021/acs.jpclett.9b02501
DO - 10.1021/acs.jpclett.9b02501
M3 - Article
C2 - 31584830
AN - SCOPUS:85073144836
SN - 1948-7185
VL - 10
SP - 6455
EP - 6461
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 21
ER -