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Exclusive Substitutional Nitrogen Doping on Graphene Decoupled from an Insulating Substrate.

ABSTRACT: The on-surface synthesis of atomically flat N-doped graphene on oxidized copper is presented. Besides circumventing the almost standard use of metallic substrates for growth, this method allows producing graphene with ∼2.0 at % N in a substitutional configuration directly decoupled from the substrate. Angle-resolved photoemission shows a linear energy-momentum dispersion where the Dirac point lies at the Fermi level. Additionally, the N functional centers can be selectively tailored in sp² substitutional configuration by making use of a purpose-made molecular precursor: dicyanopyrazophenanthroline (C₁₆H₆N₆).

SUBMITTER: Moreno-Lopez JC

PROVIDER: S-EPMC7552092 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Exclusive Substitutional Nitrogen Doping on Graphene Decoupled from an Insulating Substrate.

Moreno-López Juan Carlos JC Fedi Filippo F Argentero Giacomo G Carini Marco M Chimborazo Johnny J Meyer Jannik J Pichler Thomas T Mateo-Alonso Aurelio A Ayala Paola P

The journal of physical chemistry. C, Nanomaterials and interfaces 20200831 40

The <i>on-surface</i> synthesis of atomically flat N-doped graphene on oxidized copper is presented. Besides circumventing the almost standard use of metallic substrates for growth, this method allows producing graphene with ∼2.0 at % N in a substitutional configuration directly decoupled from the substrate. Angle-resolved photoemission shows a linear energy-momentum dispersion where the Dirac point lies at the Fermi level. Additionally, the N functional centers can be selectively tailored in sp ...[more]

PMID: 33072238

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