Ruan Xiaopeng, Shi Junqin, Wang Xiaomei, Wang William Yi, Fan Xiaoli, Zhou Feng
State Key Laboratory of Solidification Processing, Center of Advanced Lubrication and Seal Materials, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, PR China.
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000, PR China.
ACS Appl Mater Interfaces. 2021 Sep 1;13(34):40901-40908. doi: 10.1021/acsami.1c09970. Epub 2021 Aug 18.
Structural superlubricity is a fascinating physical phenomenon that plays a significant role in many scientific and technological fields. Here, we report the robust superlubricating state achieved on the interface of relatively rotated graphdiyne (GDY) bilayers; such an interface with ultralow friction is formed at nearly arbitrary rotation angles and sustained at temperatures up to 300 K. We also identified the reverse correlation between the friction coefficient and size of the Moiré lattice formed on the surface of the incommensurate stacked GDY bilayers, particularly in a small size range. Our investigations show that the ultralow friction and the reduction of the friction coefficient with the increase in size of the Moiré lattice are closely related to the interfacial energetics and charge density as well as the atomic arrangement. Our findings enable the development of a new solid lubricant with novel superlubricating properties, which facilitate precise modulation of the friction at the interface between two incommensurate contacting crystalline surfaces.
结构超润滑是一种引人入胜的物理现象，在许多科学和技术领域都发挥着重要作用。在此，我们报告了在相对旋转的石墨炔（GDY）双层界面上实现的稳健超润滑状态；这种具有超低摩擦的界面在几乎任意旋转角度下形成，并在高达300 K的温度下保持。我们还确定了在非共格堆叠的GDY双层表面形成的莫尔晶格的摩擦系数与尺寸之间的反向相关性，特别是在小尺寸范围内。我们的研究表明，超低摩擦以及摩擦系数随莫尔晶格尺寸增加而降低与界面能量学、电荷密度以及原子排列密切相关。我们的发现有助于开发具有新型超润滑性能的新型固体润滑剂，这有利于精确调节两个非共格接触晶体表面之间界面处的摩擦。
