Environmental effects on nanoscale friction at graphite basal plane and step edge
Environmental effects on nanoscale friction at graphite basal plane and step edge
复制标题
环境对石墨基面和台阶边缘纳米级摩擦的影响
DOI：
10.1016/j.apsusc.2023.157101
复制
发表时间：
2023
影响因子：
6.7
通讯作者：
Kim, Seong H.
中科院分区：
文献类型：
--
作者：
Chen, Zhe;Kim, Seong H.
石墨通常被认为是一种良好的固体润滑剂，但其作为润滑剂的有效性可能会因环境条件而异。由于与石墨的宏观接触涉及微观或纳米晶体颗粒的基面和台阶边缘，因此了解它们对环境依赖性摩擦的单独贡献至关重要。为此，本研究使用原子力显微镜与Si探针，调查吸附的水和正戊醇从气相上的石墨的基面和台阶边缘的纳米级摩擦的效果。结果表明，随着环境湿度的增加，基面摩擦力单调增加，台阶边缘摩擦力先增加后减小。吸附正戊醇后，基面和台阶边的摩擦力均减小。这些发现可能与吸附的分子在滑动界面，这改变了探针和基面之间的相称的相互作用的程度，以及探针和台阶边缘之间的瞬态化学相互作用的等温线和结构。
Graphite is typically regarded as a good solid lubricant, but its effectiveness as a lubricant can vary depending on environmental conditions. Since macroscopic contact with graphite involves both basal planes and step edges of micro- or nano-crystalline particulates, it is critical to understand their individual contributions to the environment-dependent friction. To that end, this study used atomic force microscopy with a Si probe to investigate the effect of adsorption of water and n-pentanol from the gas phase on the nanoscale friction of the basal plane and step edge of graphite. The results showed that as the ambient humidity increases, friction on the basal plane increases monotonically, while friction at the step edge first increases and then decreases. Additionally, when n-pentanol is adsorbed, the friction of both basal plane and step edge decreases. These findings could be correlated with the isotherm and structure of the adsorbed molecules in the sliding interface, which alters the degree of commensurate interactions between the probe and the basal plane, as well as the transient chemical interactions between the probe and the step edge.