Atomic simulations of effect on thermal conductivity of ion-irradiated graphene

It is an effective approach to manipulate the physical properties of graphene by defects produced by ion irradiation. In this work, we first simulate the process of ions bombardment on graphene by molecular dynamics, present the relationship between the probability of defects occurrence and the kinetic energy of incident ions. Whereafter we calculate the thermal conductivity of graphene suffering from ions irradiation by non-equilibrium molecular dynamics simulation. It is found that the thermal conductivity of graphene is remarkably suppressed by ions irradiation due to the generation of defects such as adatoms and vacancies. The underlying influence of irradiation dose and kinetic energy of incident ions on the thermal conductivity of graphene is well interpreted by the probability of defects occurrence. Our findings are helpful for understanding and tuning the thermal conductivity of graphene by defect engineering.