Bending-Induced Delamination of van der Waals Solids

TL;DR

This study investigates how bending causes delamination in multilayer van der Waals solids like graphene, revealing a critical curvature threshold and a typical delamination pattern through molecular dynamics simulations.

Contribution

It introduces a quantitative model linking curvature to delamination in van der Waals solids, supported by molecular dynamics simulations, aiding nanostructure design.

Findings

Delamination occurs below a critical radius of curvature proportional to the number of layers.

Approximately one-third of the layers tend to delaminate during bending.

A transparent model explains the delamination behavior, guiding future nanomaterial design.

Abstract

Although sheets of layered van der Waals solids offer great opportunities to custom-design nanomaterial properties, their weak interlayer adhesion challenges structural stability against mechanical deformation. Here, bending-induced delamination of multilayer sheets is investigated by molecular dynamics simulations, using graphene as an archetypal van der Waals solid. Simulations show that delamination of a graphene sheet occurs when its radius of curvature decreases roughly below $R_c=5.3\text{nm}\times (\text{number of layers})^{3/2}$ and that, as a rule, one-third of the layers get delaminated. These clear results are explained by a general and transparent model, a useful future reference for guiding the design of nanostructured van der Waals solids.