Electronic and magnetic properties of nitrogen-doped graphene nanoribbons with grain boundary

Grain boundary (GB) is a one-dimensional interface between two domains of materials with different crystallographic orientations. We investigate the effect of N-doping on the electronic and magnetic properties for hybrid graphene nanoribbon (GNR) with GB, using density functional theory. We find that substituted N atom energetically prefers to distribute at the GB as well as at the ribbon edges. The substituted N atom can induce a variable total magnetic moment depending on the doping sites. After N doping, the translational GB can be spin polarized with ferromagnetic order, and then several spin configurations are generated considering the magnetic couplings between the magnetic moments localized at the ribbon edges and linear translational GB. However, for N-doped GNR with tilt GB, the magnetic moment is extended and denser at the ribbon edges and linear GB. Moreover, small splits of some peaks at the Fermi level are also observed due to partial polarization of GB.