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Switchable graphene-substrate coupling through formation/dissolution of an intercalated Ni-carbide layer.

ABSTRACT: Control over the film-substrate interaction is key to the exploitation of graphene's unique electronic properties. Typically, a buffer layer is irreversibly intercalated "from above" to ensure decoupling. For graphene/Ni(111) we instead tune the film interaction "from below". By temperature controlling the formation/dissolution of a carbide layer under rotated graphene domains, we reversibly switch graphene's electronic structure from semi-metallic to metallic. Our results are relevant for the design of controllable graphene/metal interfaces in functional devices.

SUBMITTER: Africh C

PROVIDER: S-EPMC4726223 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Switchable graphene-substrate coupling through formation/dissolution of an intercalated Ni-carbide layer.

Africh Cristina C Cepek Cinzia C Patera Laerte L LL Zamborlini Giovanni G Genoni Pietro P Menteş Tevfik O TO Sala Alessandro A Locatelli Andrea A Comelli Giovanni G

Scientific reports 20160125

Control over the film-substrate interaction is key to the exploitation of graphene's unique electronic properties. Typically, a buffer layer is irreversibly intercalated "from above" to ensure decoupling. For graphene/Ni(111) we instead tune the film interaction "from below". By temperature controlling the formation/dissolution of a carbide layer under rotated graphene domains, we reversibly switch graphene's electronic structure from semi-metallic to metallic. Our results are relevant for the d ...[more]

PMID: 26804138

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