A Study on Stiffness of a Defective Rippled Graphene Using Molecular Dynamics Simulation

Graphene without defects exhibits extraordinary mechanical properties, while defects such as vacancies and Stone-Wales usually impose a suffering effect on graphene's properties. On the other hand, strictly two-dimensional crystals are expected to be unstable due to the thermodynamic requirement for the existence of out-of-plane bending with interatomic interaction generating a mathematical paradox. This paper researches the fracture strength and the stretching stiffness of a rippled defective graphene that is placed under the loading pressure of uniaxial tensile. With the purpose of replicating a model for carbon atoms’ covalence bonding, a molecular dynamics simulation is carried out. This is sorted according to the adaptive intermolecular reactive bond order potential function. The degree of the temperature of the system throughout the experiment is contained through the Nose-Hoover thermostat. The software package large-scale atomic/molecular massively parallel simulator is utilized for the aim of simulation the desired bond formation in the graphene layer structure. The present study offers a physical insight into the mechanisms of topological mechanical defects of graphene, and we propose static ripples as one of the key elements to accurately understand the thermo-mechanics of graphene. The results revealed that the fracture strength of a rippled graphene is significantly reduced when it contains defects, and fracture stress and strain with different vacancy defects are presented and compared.