Kinetic Monte Carlo simulations of vacancy evolution in graphene

Kinetic lattice Monte Carlo simulations, implementing ab initio calibrated energetics, are applied to study the evolution of vacancy systems in graphene. The evolution of the under-coordinated atomic layer proceeds, in general, by island nucleation and growth. However, the first stage (nucleation) is strongly influenced by the stability of small aggregates (e.g. di-vacancies) and by the effective coalescence/attachment barriers. Quantitative predictions of the system kinetics in terms of crystal state and defects' morphology as a function of the initial state and the temperature can be obtained and readily compared with experimental structural characterization of processed samples.