| AVS 64th International Symposium & Exhibition | |
| Surface Science Division | Tuesday Sessions |
| Session SS-TuP |
| Session: | Surface Science Poster Session |
| Presenter: | Brandon Blue, University of Central Florida |
| Authors: | M.S. Lodge, University of Central Florida C. Tang, University of California Merced B.T. Blue, University of Central Florida W. Hubbard, University of California at Los Angeles A. Martini, University of California Merced B. Dawson, University of Central Florida M. Ishigami, University of Central Florida |
| Correspondent: | Click to Email |
Recent simulations [Guerra et al, Nature Materials, 9, 634 (2010)] have predicted that, at high sliding speeds, gold nanocrystals slide with vanishing friction on graphite. Unlike structural or super-lubricity observed previously in nanotribology experiments, the predicted reduction of friction by two orders of magnitude was found to be independent of the commensurability between the two sliding surfaces. As such, the predicted phenomenon, named ballistic nanofriction, is novel and different from any phenomena previously observed in nanotribology.
In this talk, we present experimental evidence of ballistic nanofriction for gold nanocrystals deposited onto graphene-coated quartz crystal microbalances (QCMs) under UHV. Lubricity exceeding ballistic nanofriction is observed down to surface velocities of 4.7 cm/sec: much lower than expected from the work of Guerra et al. The observed drag coefficients are ~8.65×10−14 kg/s. This is significantly smaller than the theoretically-predicted value of 2.0×10−13 kg/s, and suggests a much lower interaction strength between graphene and gold nanocrystals than previously assumed in contemporary theoretical models of gold nanocrystals on graphite.
Acknowledgements: This work is based upon research supported by the National Science Foundation under Grant No. 0955625 (MLS, BTB, BDD and MI) and Grant No. CMMI-1265594 (CT and AM). BDD and MI were also supported by the Intelligence Community Postdoctoral Fellowship.