论文标题
在几层和散装掺杂mos $ _2 $中滑动的原子机制
Atomistic Mechanisms of Sliding in Few-Layer and Bulk Doped MoS$_2$
论文作者
论文摘要
二维材料的滑动对于它们作为空间固体润滑剂的应用至关重要，并且与应变工程和设备制造有关。尽管NI形成了层间键，但诸如NI之类的掺杂剂令人惊讶地改善了MOS $ _2 $的润滑，并且该机制尚不清楚。理论上已经在原子材料的2D材料中对原子水平的滑动进行了研究，但在掺杂的形式上几乎没有工作，尤其是对于复杂的插入情况。我们使用密度功能理论来研究Ni掺杂的MOS $ _2 $的滑动，考虑到mo/s的替代和八面体/四面体插入。我们发现成对双层相互作用很好地描述了散装和三利叶。层之间的四面体插入大大增加了其滑动屏障，但最小化影响在相邻的未木质层之间滑动，从而保留有效的润滑。我们提供了一种原子观点，说明在掺杂的过渡金属二分法中的滑动方式以及一种分析掺杂滑动的一般方法。
Sliding of two-dimensional materials is critical for their application as solid lubricants for space, and also relevant for strain engineering and device fabrication. Dopants such as Ni surprisingly improve lubrication in MoS$_2$, despite formation of interlayer bonds by intercalated Ni, and the mechanism has remained unclear. While sliding on the atomistic level has been theoretically investigated in pristine 2D materials, there has been little work on doped forms, especially for the complicated case of intercalation. We use density functional theory to study sliding of Ni-doped MoS$_2$, considering Mo/S substitution and octahedral/tetrahedral intercalation. We find that bulk and trilayers are well described by pairwise bilayer interactions. Tetrahedral intercalation between layers dramatically increases their sliding barrier, but minimally affects sliding between adjacent undoped layers, thus preserving effective lubrication. We provide an atomistic view of how sliding occurs in doped transition-metal dichalcogenides, and a general methodology to analyze doped sliding.
