Electronic and magnetic properties of bilayer graphene with intercalated adsorption atoms C, N and O

TL;DR

This study uses ab-initio density functional theory to explore how intercalated C, N, and O atoms affect the electronic and magnetic properties of bilayer graphene, revealing atom-specific adsorption sites and magnetism.

Contribution

It provides new insights into the preferred adsorption sites and magnetic behaviors of C, N, and O atoms in bilayer graphene, which were not previously detailed.

Findings

N and O favor bridge sites; C prefers hollow site.

N induces full spin polarization and magnetism.

C and N cause Fermi level shifts, leading to metallic behavior.

Abstract

We present an ab-initio density function theory to investigate the electronic and magnetic structures of the bilayer graphene with intercalated atoms C, N, and O. The intercalated atom although initially positioned at the middle site of the bilayer interval will finally be adsorbed to one graphene layer. Both N and O atoms favor the bridge site (i.e. above the carbon-carbon bonding of the lower graphene layer), while the C atom prefers the hollow site (i.e. just above a carbon atom of the lower graphene layer and simultaneously below the center of a carbon hexagon of the upper layer). Concerning the magnetic property, both C and N adatoms can induce itinerant Stoner magnetism by introducing extended or quasilocalized states around the Fermi level. Full spin polarization can be obtained in N-intercalated system and the magnetic moment mainly focuses on the N atom. In C-intercalated system, both the foreign C atom and some carbon atoms of the bilayer graphene are induced to be spin-polarized. N and O atoms can easily get electrons from carbon atoms of bilayer graphene, which leads to Fermi level shifting downward to valence band and thus producing the metallic behavior in bilayer graphene.