A theoretical investigation of two-dimensional graphene-Cr-graphene intercalation nanostructures has been carried out using density functional theory (DFT) calculations. The intercalation nanostructures of interest are classified based on the atomic ratio of Cr with respect to C on two graphene layers, and we accordingly assign nomenclatures to the intercalation nanostructures as 1-4, 1-12, and 1-16 GMG. Binding energy analysis suggests that the 1-12 and 1-16 GMG structures are energetically stable, whereas the 1-4 GMG structure is unstable. When examining the 1-4 bilayer graphene-Cr (GGM) structure, we have found that it is energetically stable and nonmagnetic. On the other hand, all three GMG intercalation structures are found to be ferromagnetic, and the 1-16 GMG structure exhibits the highest total magnetization (2.00 μB/cell), whereas the 1-12 GMG structure exhibits the lowest total magnetization (0.46 μB/cell). Interplays between stability and magnetic properties of these three nanostructures are discussed from electronic structure analysis. It is found for the two stable nanostructures that the 2pz orbitals of graphene layers are aligned antiferromagnetically with respect to the Cr layer, thus causing negative contributions to total magnetic moments of two stable GMG nanostructures.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films