Electronic properties of graphene nanoribbons with periodical nanoholes passivated by oxygen

Abstract

By using the first-principles method and the density-functional theory, the electronic properties of graphene nanoribbons(GNRs) with periodic nanoholes passivated by oxygen are studied. It is shown that for the zigzag graphene nanoribbon (ZGNR) in nonmagnetic state(NM), the metallic properties not only still remain but also are obviously enhanced after the holes are punched. But for the antiferromagnetic-state (AFM) ZGNR, after punching holes, it would be changed from semiconductor to metal. While for the ferromagnetic-state (FM) ZGNR, it can be transformed from metal to semiconductor or semimetal after punching holes. Besides, for the punched armchair graphene nanoribbon (AGNR), its band gap will be significantly widened. The in-depth analysis shows that these results are due to the effects of oxygen atoms on electronic properties of GNRs, and also due to the different quantum confinement effects from the neck subprime nanoribbon (NSNR) and edge subprime nanoribbon (ESNR) with different width and edge shape(zigzag or armchair). These findings are important for developing nano electronic devices.