Half metallicity in bare BC₂N nanoribbons with zigzag edges

We study the electronic and magnetic properties of bare zigzag BC₂N nanoribbons (ZBC₂NNRs) by using first principles calculations. The ZBC₂NNRs which we studied are assigned to four edge types, and we carefully examine the size effect and edge magnetic coupling orders. We find that the N edge and the C edge adjacent to N atoms have a ferromagnetic coupling, while the B edge and the C edge adjacent to B atoms have an anti-ferromagnetic coupling. These novel properties arise from the unsaturated edge with specific edge determined magnetic moment distribution. All the investigated ribbons exhibit magnetic ground states with room-temperature accessible half-metallic character, irrespective of the ribbon width. Our results suggest that ZBC₂NNRs can have potential applications in spintronics. - Highlights: • DFT study on bare zigzag BC₂N nanoribbons (ZBC₂NNRs). • All the studied bare ZBC₂NNRs are half-metals at room temperature. • The half-metal characters come from specific spin couplings on the edge atoms. • We predict bare ZBC₂NNRs as practical candidate for spintronics.