Manipulation of mechanical properties of monolayer molybdenum disulfide: Kirigami and hetero-structure based approach

Abstract

The two-dimensional monolayer structure of molybdenum disulfide (MoS2) is widely used in the advanced flexible electronic devices due to their unique mechanical, physical, and electronic properties. The main disadvantage of MoS2 is the limited mechanical strain, which restricts its application in flexible and stretchable devices. Therefore, it is required to develop various methods to modify the mechanical behavior of MoS2 monolayer depending on the environmental situation and the complexity of real applications. In this investigation, we have incorporated Kirigami and hetero-structure approaches for the manipulation of the mechanical behavior of MoS2. Kirigami is an ancient Japanese art of paper cutting. Monolayer MoS2 with circular/square/rectangular Kirigami pattern have simulated under uniaxial tensile load using molecular dynamics simulation. We observe that the stretch-ability (mechanical strain) significantly enhanced by the shape/size and location of Kirigami pattern during uniaxial tensile deformation. However, strength (mechanical stress and Young's modulus) of MoS2 can be enhancing by creating a hetero-structure with graphene. A large number of simulations have been performed to explore stress/energy distribution, Young's modulus, the effect of temperature, and strain rate during load applications. We believe that our results will provide extensive information related to enhancement in the mechanical strain and strain toward the application in flexible devices.