▎ 摘　　要

Using density functional theory, we consider the adsorption of C on graphene, which gives rise to many interesting phenomena. A single-C at the bridge site shows a clearly covalent-bond feature with graphene, in which the metallic state occurs and a magnetic moment of 0.36 mu(B) was determined. For both-sided adsorption, the magnetic moment is remarkably larger than that in one-sided adsorption, and increases with concentration up to a coverage of 12.5%. High spin polarization obtained at the Fermi level indicates a high degree of passage of preferred spin, which is important for developing spin filters.