Electronic and magnetic properties of zigzag α-graphyne nanoribbons with edge fluorine modification

Abstract

Using the first principles calculations, we investigate the stability of hydrogen, fluorine and oxygen atoms saturated the edge of zigzag α-graphyne nanoribbons (ZαGYNRs), and find edge fluorination is the most stable one. Then we probe the magnetic properties and electronic structures of three different edge fluorinated ZαGYNRs. The results show that the magnetic properties and band structures have a close relationship with the edge fluorinated manners. For the symmetric edge fluorination: (1) Monofluorinated ZαGYNRs shows spin-degenerated semiconductor property in the ground state (antiferromagnetic state). (2) For difluorinated ZαGYNRs, the magnetism and band structures are relying on the ribbon width. It shows nonmagnetic semiconductor property when the ribbon width is smaller than 6. Otherwise, it shows spin-degenerated semiconductor property in its ground state (antiferromagnetic state). While the asymmetric edge fluorination can break the spin-degeneracy and introduce 1μB magnetic moment for ZαGYNRs in its ground state (ferromagnetic state), making the system shows bipolar magnetic semiconductor property. All these results are beneficial for designing spin semiconductor devices.