IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Tribology Wednesday Sessions
       Session TR+MM-WeA

Paper TR+MM-WeA5
Interfacial Friction of Methanol Sliding on Rigid vs. Rotating Fullerenes

Wednesday, October 31, 2001, 3:20 pm, Room 132

Session: Nanotribology
Presenter: T.S. Coffey, North Carolina State University
Authors: T.S. Coffey, North Carolina State University
M. Abdelmaksoud, North Carolina State University
J. Krim, North Carolina State University
Correspondent: Click to Email
Due to the ability of C60 molecules to rapidly rotate within their lattice position, tribologists had hopes that C60 molecules would work like nano-sized ball bearings. C60 has not been proven to be an effective lubricant. We measured the interfacial friction of toluene on Ag(111) in both the presence and absence of interfacial C60 layers employing quartz crystal microbalance (QCM) and atomic force microscopy (AFM) techniques.@footnote 1@ We see the friction double when C60 is present. However, the difference in interfacial friction between a rigid vs. a rotating molecule in a substrate remains an interesting topic. C60 is known to form close packed hexagonal films on both Ag(111) and Cu(111) substrates. However, on Ag(111) surfaces, C60 is known to spin freely in its lattice position, while it is not free to rotate on a Cu(111) surface.@footnote 2@ In order to determine whether the spinning of the C60 molecules affects the interfacial friction, we are employing QCM techniques to compare the friction of methanol on C60/Ag(111) vs. methanol on C60/Cu(111). We examine here whether the rolling nature of the C60 layer impacts the sliding friction as probed by QCM, AFM, and QCM/STM measurements. @FootnoteText@ @footnote 1@ T. Coffey, M. Abdelmaksoud, and J. Krim, "A Scanning Probe and Quartz Crystal Microbalance Study of the Impact of C60 on Friction at Solid-Liquid Interfaces", Journal of Physics Condensed Matter, in press. @footnote 2@ Applied Surface Science 87/88 (1995) 405.