Shear Strain-Induced Two-Dimensional Slip Avalanches in Rhombohedral MoS2

Nano Lett. 2023 Aug 9;23(15):7228-7235. doi: 10.1021/acs.nanolett.3c01487. Epub 2023 Jun 26.

Abstract

Slip avalanches are ubiquitous phenomena occurring in three-dimensional materials under shear strain, and their study contributes immensely to our understanding of plastic deformation, fragmentation, and earthquakes. So far, little is known about the role of shear strain in two-dimensional (2D) materials. Here we show some evidence of 2D slip avalanches in exfoliated rhombohedral MoS2, triggered by shear strain near the threshold level. Utilizing interfacial polarization in 3R-MoS2, we directly probe the stacking order in multilayer flakes and discover a wide variety of polarization domains with sizes following a power-law distribution. These findings suggest that slip avalanches can occur during the exfoliation of 2D materials, and the stacking orders can be changed via shear strain. Our observation has far-reaching implications for the development of new materials and technologies, where precise control over the atomic structure of these materials is essential for optimizing their properties as well as for our understanding of fundamental physical phenomena.

Keywords: 2D materials; ferroelectricity; mechanical exfoliation; shear strain; slip avalanche.