Transition Metal Adsorption Promotes Patterning and Doping of Graphene by Electron Irradiation

We present an ab initio molecular dynamics study of the effect of transition metal (TM) adatoms (Sc-Zn) on the threshold displacement energy (TDE) of graphene. Our calculations predict that it is substantially easier to displace one of the carbon atoms near the adatoms. Substitutional TM atoms at carbon vacancies and Stone-Wales defects are the main defect structures formed after irradiation in the TM adatoms-graphene systems. Defect can be formed at low energy electron irradiation (electron energy below 55 keV for the V, Cr, Mn, Fe, and Co adatoms). Thus, the absorption of TM atoms on graphene enables patterning the graphene by controlling deposition and electron irradiation, as well as graphene modification under transmission electron microscope condition. Also, the result provides an easy pathway to dope the graphene with TM substitutional atoms for the spin-electronic devices through electron-beam or ion-beam lighography.