Stability and electronic properties of the graphene-supported FeO nanostructures including clusters and monolayer

Highlights: • Stability and electronic properties of FeO nanostructures on graphene are investigated. • Formation of Fe–C bonds at the interface provide stability to the nanosystems on graphene. • Substrate-induced changes in electronic properties of the (FeO)${}_n$ clusters are small. • FeO monolayer changes from antiferromagnetic insulator to ferrimagnetic metal on graphene surface. Integration of graphene with subnano clusters or monolayer of FeO can facilitate the formation of nanostructures with applications in magnetic storage or health-related areas. In this paper, first-principles calculations are performed to investigate the stability and electronic properties of such supported nanostructures. The results show that a noticeable hybridization occurs between Fe and C atoms at the interface that provide stability to both the clusters and monolayer on graphene. The substrate-induced changes in the electronic properties of the (FeO)${}_n$ clusters are small since the clusters appeared to be weakly adsorbed on the surface. However, this is not the case with FeO(111) monolayer for which a buckled configuration is predicted to be energetically preferred on graphene. Subsequently, graphene-supported FeO(111) monolayer exhibits half-metallicity with ferrimagnetic alignment of the magnetic moments in the lattice with finite total magnetic moment. The interface bonding, therefore, appears to define the characteristics of graphene-supported FeO(111) monolayer, though it makes small but noticeable changes in the graphene-supported (FeO)${}_n$ clusters.