Influence of Temperature, Strain Rate, and Vacancies on the Mechanical Properties of Aluminum-Doped Bilayer Silicene

Abstract

Silicene, a two-dimensional material with promising potential for future technological applications, has attracted considerable attention over the past decade. Recent research has focused on modifying silicene's electronic and magnetic properties by means of adsorption or substitutional doping. While the magnetic, electronic, and optical properties of doped silicene have been extensively studied, there is a noticeable gap in the literature regarding its mechanical properties. To address this issue, this study explores the mechanical characteristics of bilayer silicene doped with aluminum under various conditions. By employing molecular dynamics simulations, we investigate the influence of aluminum concentration, defects, temperature, and strain rate on the material's mechanical response. The findings reveal a monotonically decreasing strength with Al concentration in both the zigzag and armchair straining directions. Additionally, the material exhibits high sensitivity to defects, with even a small percentage significantly impairing its mechanical properties. Directional dependence is also observed, with the zigzag direction showing greater sensitivity than the armchair. As strain progresses, initial mono-vacancies evolve into more complex defects, hindering predictions of the mechanical response in certain cases. Lastly, strain rate sensitivity is evaluated, yielding values of 0.0485 and 0.0365 for the zigzag and armchair directions, respectively.