Single-Layer MoS2: A Two-Dimensional Material with Negative Poisson's Ratio

Negative Poisson's ratio (NPR) materials have broad applications such as heat dissipation, vibration damping, and energy absorption because of their designability, lightweight quality, and high strength ratio. Here, we use first-principles calculations to find a two-dimensional (2D) auxetic material (space group R3 over bar m), which exhibits a maximum in-plane NPR of -0.0846 and a relatively low Young's modulus in the planar directions. Calculations show that the NPR is mainly related to its unique zigzag structure and the strong interaction between the 4d orbital of Mo and the 3p orbital of S. In addition, molecular dynamics (MD) simulations show that the structure of this material is thermodynamically stable. Our study reveals that this layered MoS2 can be a promising 2D NPR material for nanodevice applications.

Automated summary

In this study, a two-dimensional material (space group R3 over bar m) with a negative Poisson's ratio (NPR) and a maximum NPR of -0.0846 in-plane was discovered using first-principles calculations. The NPR is mainly attributed to its unique zigzag structure and the strong interaction between Mo's 4d orbital and S's 3p orbital. Molecular dynamics simulations indicate the thermodynamic stability of this material. This research reveals the potential of layered MoS2 as a promising 2D NPR material for nanodevice applications.