First-principles study of half-metallicity in semi-hydrogenated BC(3), BC(5), BC(7), and B-doped graphone sheets

Using first principles calculations, we investigate the electronic structures of semi-hydrogenated BC(3), BC(5), BC(7), and B-doped graphone sheets. We find that all the semi-hydrogenated boron-carbon sheets exhibit half-metallic behaviors. The magnetism originates from the non-bonding p(z )orbitals of carbon atoms, which cause the flat bands to satisfy the Stoner criterion. On the other hand, boron atoms weaken the magnetic moments of nearby carbon atoms and act as holes doped in the sheets. It induces the down shift of the Fermi level and the half-metallicity in semi-hydrogenated sheets. Our studies demonstrate that the semi-hydrogenation is an effective route to achieve half-metallicity in the boron-carbon systems.