Effects of Stone-Wales and vacancy defects in atomic-scale friction on defective graphite

作者：Xiaoyu Sun, Runni Wu, Re Xia, Xihua Chu, Yuanjie Xu · 发表于：Applied Physics Letters · 年份：2014 · DOI：10.1063/1.4876055 · 被引用次数：44 · 研究领域：Graphene research and applications、Force Microscopy Techniques and Applications、Diamond and Carbon-based Materials Research

Graphite is an excellent solid lubricant for surface coating, but its performance is significantly weakened by the vacancy or Stone-Wales (SW) defect. This study uses molecular dynamics simulations to explore the frictional behavior of a diamond tip sliding over a graphite which contains a single defect or stacked defects. Our results suggest that the friction on defective graphite shows a strong dependence on defect location and type. The 5-7-7-5 structure of SW defect results in an effectively negative slope of friction. For defective graphite containing a defect in the surface, adding a single vacancy in the interior layer will decrease the friction coefficients, while setting a SW defect in the interior layer may increase the friction coefficients. Our obtained results may provide useful information for understanding the atomic-scale friction properties of defective graphite.