Mechanical Properties of MoS2/Graphene Heterostructures

TL;DR

This study uses molecular dynamics simulations to compare the mechanical properties of MoS2 and graphene/MoS2/graphene heterostructures, revealing how layering affects stiffness and strain behavior.

Contribution

It provides new insights into how graphene layers influence the mechanical properties of MoS2 in heterostructures, especially regarding stiffness enhancement and strain limits.

Findings

Young's modulus of MoS2 increased fivefold in heterostructure

Lattice mismatch causes spontaneous interface strain energy

Yield strain decreases due to lateral buckling of graphene layers

Abstract

We perform classic molecular dynamics simulations to comparatively investigate the mechanical properties of single-layer MoS2 and a graphene/MoS2/graphene heterostructure under uniaxial tension. We show that the lattice mismatch between MoS2 and graphene will lead to an spontaneous strain energy in the interface. The Young's modulus of MoS2 can be enhanced by a factor of five by sandwiching it between two graphene layers. While the stiffness is enhanced, the yield strain of the MoS2 is reduced due to lateral buckling of the outer graphene layers due to the applied mechanical tension.