Tribological behavior of van der Waals heterostructures under incomplete contact

Abstract

Exploring tribological behavior of two-dimensional materials and structures is highly critical for evaluating surface properties and designing functional surfaces with outstanding wear resistance and stable superlubricity. However, the tribological response of van der Waals heterostructures remains unclear, which hinders service performance and durability of various practical and potential nanodevices. Herein, the tribological behavior of van der Waals heterostructures under incomplete contact is explored by using molecular dynamics simulation and theoretical analysis. The corresponding instantaneous frictional force, average frictional force, as well as the distribution of interfacial stress affected by geometric and material parameters are uncovered. It is found that the introduction of vdW heterostructures into contact pairs under incomplete contact is helpful for reducing stress concentration during the sliding process. As for the cases with remnant water, a pronounced fluctuation of instantaneous frictional force and an increased average frictional force can be observed. What is more, the tribological properties of the vdW heterostructures can be well tuned by adjusting various geometric and material parameters. The findings provide valuable insights for both the design of van der Waals heterostructure-based nanodevices and the advancement of nanotribology.