Friction fluctuations of gold nanoparticles in the superlubric regime
Friction fluctuations of gold nanoparticles in the superlubric regime
复制标题
DOI：
10.1088/1361-6528/aaac21
复制
发表时间：
2018-04-13
期刊：
影响因子：
3.5
通讯作者：
Schirmeisen, Andre
中科院分区：
文献类型：
--
作者：
Dietzel, Dirk;de Wijn, Astrid S.;Schirmeisen, Andre
超润滑性，或可替代地称为结构（超）润滑性，是一个概念，其中如果这些表面不相称并且因此不能互锁，则在滑动表面之间的界面处预期超低摩擦。在这项工作中，我们现在报告的突然，可逆的，摩擦的变化，已经观察到在AFM为基础的纳米操纵实验的金纳米粒子在高度取向的热解石墨上滑动。这些效应可以通过结构超润滑性概念内的金纳米颗粒的旋转来解释，其中超低摩擦的发生可以极其敏感地取决于滑块和基板之间的相对取向。从我们的理论模拟中，我们将清楚地看到，即使是微小的旋转幅度也与所观察到的效应相一致，以及颗粒的大小和形状如何影响摩擦力和相对取向之间的依赖关系。
Superlubricity, or alternatively termed structural (super)lubrictiy, is a concept where ultra-low friction is expected at the interface between sliding surfaces if these surfaces are incommensurate and thus unable to interlock. In this work, we now report on sudden, reversible, friction changes that have been observed during AFM-based nanomanipulation experiments of gold nanoparticles sliding on highly oriented pyrolythic graphite. These effects can be explained by rotations of the gold nanoparticles within the concept of structural superlubricity, where the occurrence of ultra-low friction can depend extremely sensitively on the relative orientation between the slider and the substrate. From our theoretical simulations it will become apparent how even miniscule magnitudes of rotation are compatible to the observed effects and how size and shape of the particles can influence the dependence between friction and relative orientation.