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Introducing carbon diffusion barriers for uniform, high-quality graphene growth from solid sources.

ABSTRACT: Carbon diffusion barriers are introduced as a general and simple method to prevent premature carbon dissolution and thereby to significantly improve graphene formation from the catalytic transformation of solid carbon sources. A thin Al2O3 barrier inserted into an amorphous-C/Ni bilayer stack is demonstrated to enable growth of uniform monolayer graphene at 600 °C with domain sizes exceeding 50 μm, and an average Raman D/G ratio of <0.07. A detailed growth rationale is established via in situ measurements, relevant to solid-state growth of a wide range of layered materials, as well as layer-by-layer control in these systems.

SUBMITTER: Weatherup RS

PROVIDER: S-EPMC3813970 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Introducing carbon diffusion barriers for uniform, high-quality graphene growth from solid sources.

Weatherup Robert S RS Baehtz Carsten C Dlubak Bruno B Bayer Bernhard C BC Kidambi Piran R PR Blume Raoul R Schloegl Robert R Hofmann Stephan S

Nano letters 20130927 10

Carbon diffusion barriers are introduced as a general and simple method to prevent premature carbon dissolution and thereby to significantly improve graphene formation from the catalytic transformation of solid carbon sources. A thin Al2O3 barrier inserted into an amorphous-C/Ni bilayer stack is demonstrated to enable growth of uniform monolayer graphene at 600 °C with domain sizes exceeding 50 μm, and an average Raman D/G ratio of <0.07. A detailed growth rationale is established via in situ me ...[more]

PMID: 24024736

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