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Edge Effects on the Electronic Structures of Chemically Modified Armchair Graphene Nanoribbons

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 نشر من قبل Li Qunxiang
 تاريخ النشر 2007
  مجال البحث فيزياء
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In this paper, we apply the first-principle theory to explore how the electronic structures of armchair graphene nanoribbons (AGNRs) are affected by chemical modifications. The edge addends include H, F, N, NH$_{2}$, and NO$_{2}$. Our theoretical results show that the energy gaps are highly tunable by controlling the widths of AGNRs and addends. The most interesting finding is that N-passivated AGNRs with various widths are metallic due to the unique electronic features of N-N bonds. This property change of AGNRs (from semiconducting to metallic) is important in developing graphene-based devices.



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