INTERCALATION OF COBALT UNDERNEATH A MONOLAYER OF GRAPHENE ON Ru(0001)

Scanning tunneling microscopy is used to study intercalation of cobalt underneath a graphene layer on Ru(0001). Deposition of cobalt on graphene/Ru(0001) at 873K leads to the intercalation of cobalt between the graphene layer and the Ru(0001) substrate, and the intercalation is associated with Co diffusion at steps and defects. The morphology of graphene/Co/Ru(0001) shows moire pattern, as same as that of graphene/Ru(0001). The bright areas where Co islands exist are hcp regions of graphene/Ru(0001). The intercalated Co islands have a pseudomorphic structure superimposed on Ru(0001).