Mechanical Response of Buckled Germanene: Influence of Temperature, Strain Rate and Point Defects

Abstract

Germanene, a two-dimensional material with a unique buckled honeycomb structure, has recently drawn attention for its potential in nanoelectromechanical systems (NEMS) and advanced nano-devices. In this work, we explore how temperature, strain rate, and point defects influence its mechanical performance through molecular dynamics simulations. The findings show that as temperature rises, the fracture stress, strain, and elastic modulus drop sharply by as much as 66% due to stronger atomic vibrations and thermal softening. In contrast, faster strain rates significantly improve these properties, enhancing strength by nearly 45% because atoms have less time to relax. The presence of point vacancies, even in small amounts, weakens the structure considerably, as these defects act as stress concentrators that trigger early fracture. Interestingly, a clear anisotropy is observed: the zigzag direction offers higher strength, while the armchair direction remains more flexible. Overall, the study provides valuable insights into how germanene responds under different conditions and highlights its promise as a durable and tunable material for next-generation nanoelectronic and electromechanical devices.