Electronic and magnetic properties for Co13 clusters deposited on graphene: A first-principles exploration

First-principles calculations were carried out to explore the geometry, energetic stability and magnetic property of cobalt nanoclusters adsorbed on graphene. Three structural isomers of Co13 clusters (icosahedron, fcc, and hcp) were chosen as model systems for ferromagnetic nanoclusters. The adsorption energies for these three types of Co13 clusters supported on graphene range between 1.66 and 2.21 eV. Both binding energy and adsorption energy first decrease with reducing coverage and then converge to invariant values at the coverage of 21.7%, which is originated from the interaction between the Co13 cluster and its periodic images. Regardless the detailed cluster configuration, the cluster–graphene interaction reduces the magnetic moment of the Co13 cluster by ∼20% compared with its free-standing counterpart. Most importantly, induced magnetic moments of graphene due to Co13 adsorption were observed, which may offer a new opportunity to tune the magnetic properties of graphene for its device applications.

► Chemical adsorption between the Co13 cluster and the graphene was predicted.
► Both the binding and adsorption energies converge to a constant for R<21.7%.
► Formation of CoC carbide reduces magnetic moment of the Co13 cluster by ∼20%.
► Induced magnetic moments of graphene for adsorption of Co13 clusters were found.