Mechanical characteristics and failure behavior of puckered and buckled allotropes of antimonene nanotubes: a molecular dynamics study

Abstract

In recent years, antimonene nanotubes have attracted considerable interest for diverse applications owing to their promising physical properties. In this study, classical molecular dynamics simulations with Stillinger–Weber potential were carried out to explore the fundamental mechanical characteristics of two stable allotropes of antimonene nanotubes (SbNTs), namely puckered (α-) and buckled (β-) nanotubes. Mechanical properties and deformation mechanisms of antimonene nanotubes, including ultimate tensile strength, fracture strain, and Young's modulus, were thoroughly examined by considering chirality, diameter, temperature, and strain rate variables. Numerical simulations revealed that all SbNT specimens examined in this study exhibit brittle failures with a complete loss of load-bearing capability following the ultimate stress level. The brittle nature of the SbNTs with varied diameters remained unchanged under different temperatures and loading-rate conditions. Owing to their distinct crystal structure in the armchair and zigzag directions, α-SbNTs present a distinctive anisotropic behavior compared to β-SbNTs. While the variation of the elastic modulus with temperature is not notable, the tensile strength and fracture strain of SbNTs deteriorated considerably at high temperatures. Furthermore, it was observed that the effects of diameter and temperature on zigzag α-SbNT are more pronounced due to its lower stability. Altogether, this study presents a comprehensive examination of the mechanical characteristics of the two stable antimonene allotropes and provides useful information for their potential utilizations in a wide range of applications.