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arXiv · 1306.5467

Electronic structure of oxygen-functionalized armchair graphene nanoribbons

Adam J. Simbeck·Deyang Gu·Neerav Kharche·Parlapalli Venkata Satyam·Phaedon Avouris·Saroj K. Nayak
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Abstract

The electronic and magnetic properties of varying width, oxygen-functionalized armchair graphene nanoribbons (AGNRs) are investigated using first-principles density functional theory (DFT). Our study shows that O-passivation results in a rich geometrical environment which in turn determines the electronic and magnetic properties of the AGNR. For planar systems a degenerate magnetic ground state, arising from emptying of O lone-pair electrons, is reported. DFT predicts ribbons with ferromagnetic coupling to be metallic whereas antiferromagnetically coupled ribbons present three band gap families: one metallic and two semiconducting. Unlike hydrogen functionalized AGNRs, the oxygen functionalized ribbons can attain a lower energy configuration by adopting a non-planar geometry. The non-planar structures are non-magnetic and show three semiconducting families of band gap behavior. Quasiparticle corrections to the DFT results predict a widening of the band gaps for all planar and non-planar, semiconducting systems. This suggests that oxygen functionalization could be used to manipulate the electronic structures of AGNRs.

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Adam J. Simbeck, Deyang Gu, Neerav Kharche, Parlapalli Venkata Satyam, Phaedon Avouris, Saroj K. Nayak. 2013-06-23. Electronic structure of oxygen-functionalized armchair graphene nanoribbons. https://doi.org/10.1103/physrevb.88.035413

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