Effect of defects on Young's modulus of graphene sheets: a molecular dynamics simulation

The effect of defects including vacancy and Stone-Wales (SW) defects on the Young's modulus of graphene sheets is investigated using molecular dynamic (MD) simulations. The simulations show that the presence of defects reduces the Young's modulus of graphene sheets and Young's modulus decreases with increasing degree of defects. In addition, the vacancy defects bring about a decrease in the Young's modulus, but their reconstruction is an important factor in stabilizing the modulus. Furthermore, we explore the Young's modulus of graphene with defects functionalized by hydrogen atoms and find that the hydrogenation of vacancy defects can increase the Young's modulus of the defective graphene but the hydrogenation of SW defects has the opposite effect.