Electronic mechanism behind the influence of intercalated heteroatom Sn on the slip energy barrier in layered WS2

• Published in: Nanotechnology Vol. 36; no. 22
• Main Authors: Huang, Dulin, Shao, Gonglei, Zhang, Xu, Zhou, Zhen
• Format: Journal Article
• Language: English
• Published: IOP Publishing 02.06.2025
• Subjects: sliding energy barrier; total charge density
• ISSN: 0957-4484; 1361-6528; 1361-6528
• DOI: 10.1088/1361-6528/add166

Frictional losses between mechanical components have posed a longstanding challenge. The application of effective lubricants can markedly mitigate these losses. Recently, layered materials have garnered extensive research interest due to their superior lubricating properties. While studies on the lubrication mechanisms between interlayer atoms are increasingly common, the exploration of sliding mechanisms associated with intercalated foreign atoms in layered materials remains a subject of considerable uncertainty. In this work, we employed density functional theory (DFT) to investigate the sliding behavior of WS2 intercalated with different concentrations of heteroatom Sn atoms. The results indicate that the intercalation of Sn atoms effectively reduces the sliding barrier. As the concentration of intercalated Sn atoms increases, the enhanced electrostatic repulsion due to the increasing interlayer charge, combined with the gradual reduction in the total charge density fluctuation during the sliding process, leads to a decrease in the sliding energy barrier. Furthermore, with higher Sn atom concentrations, we observe a significant reduction in both friction force and shear strength.&#xD.Frictional losses between mechanical components have posed a longstanding challenge. The application of effective lubricants can markedly mitigate these losses. Recently, layered materials have garnered extensive research interest due to their superior lubricating properties. While studies on the lubrication mechanisms between interlayer atoms are increasingly common, the exploration of sliding mechanisms associated with intercalated foreign atoms in layered materials remains a subject of considerable uncertainty. In this work, we employed density functional theory (DFT) to investigate the sliding behavior of WS2 intercalated with different concentrations of heteroatom Sn atoms. The results indicate that the intercalation of Sn atoms effectively reduces the sliding barrier. As the concentration of intercalated Sn atoms increases, the enhanced electrostatic repulsion due to the increasing interlayer charge, combined with the gradual reduction in the total charge density fluctuation during the sliding process, leads to a decrease in the sliding energy barrier. Furthermore, with higher Sn atom concentrations, we observe a significant reduction in both friction force and shear strength.&#xD.