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Spatially resolved electronic structures of atomically precise armchair graphene nanoribbons.

ABSTRACT: Graphene has attracted much interest in both academia and industry. The challenge of making it semiconducting is crucial for applications in electronic devices. A promising approach is to reduce its physical size down to the nanometer scale. Here, we present the surface-assisted bottom-up fabrication of atomically precise armchair graphene nanoribbons (AGNRs) with predefined widths, namely 7-, 14- and 21-AGNRs, on Ag(111) as well as their spatially resolved width-dependent electronic structures. STM/STS measurements reveal their associated electron scattering patterns and the energy gaps over 1 eV. The mechanism to form such AGNRs is addressed based on the observed intermediate products. Our results provide new insights into the local properties of AGNRs, and have implications for the understanding of their electrical properties and potential applications.

SUBMITTER: Huang H

PROVIDER: S-EPMC3523290 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Spatially resolved electronic structures of atomically precise armchair graphene nanoribbons.

Huang Han H Wei Dacheng D Sun Jiatao J Wong Swee Liang SL Feng Yuan Ping YP Neto A H Castro AH Wee Andrew Thye Shen AT

Scientific reports 20121217

Graphene has attracted much interest in both academia and industry. The challenge of making it semiconducting is crucial for applications in electronic devices. A promising approach is to reduce its physical size down to the nanometer scale. Here, we present the surface-assisted bottom-up fabrication of atomically precise armchair graphene nanoribbons (AGNRs) with predefined widths, namely 7-, 14- and 21-AGNRs, on Ag(111) as well as their spatially resolved width-dependent electronic structures. ...[more]

PMID: 23248746

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