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Nucleation control for large, single crystalline domains of monolayer hexagonal boron nitride via Si-doped Fe catalysts.

ABSTRACT: The scalable chemical vapor deposition of monolayer hexagonal boron nitride (h-BN) single crystals, with lateral dimensions of ?0.3 mm, and of continuous h-BN monolayer films with large domain sizes (>25 ?m) is demonstrated via an admixture of Si to Fe catalyst films. A simple thin-film Fe/SiO2/Si catalyst system is used to show that controlled Si diffusion into the Fe catalyst allows exclusive nucleation of monolayer h-BN with very low nucleation densities upon exposure to undiluted borazine. Our systematic in situ and ex situ characterization of this catalyst system establishes a basis for further rational catalyst design for compound 2D materials.

SUBMITTER: Caneva S

PROVIDER: S-EPMC4358078 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Nucleation control for large, single crystalline domains of monolayer hexagonal boron nitride via Si-doped Fe catalysts.

Caneva Sabina S Weatherup Robert S RS Bayer Bernhard C BC Brennan Barry B Spencer Steve J SJ Mingard Ken K Cabrero-Vilatela Andrea A Baehtz Carsten C Pollard Andrew J AJ Hofmann Stephan S

Nano letters 20150217 3

The scalable chemical vapor deposition of monolayer hexagonal boron nitride (h-BN) single crystals, with lateral dimensions of ∼0.3 mm, and of continuous h-BN monolayer films with large domain sizes (>25 μm) is demonstrated via an admixture of Si to Fe catalyst films. A simple thin-film Fe/SiO2/Si catalyst system is used to show that controlled Si diffusion into the Fe catalyst allows exclusive nucleation of monolayer h-BN with very low nucleation densities upon exposure to undiluted borazine. O ...[more]

PMID: 25664483

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Single Crystalline Film of Hexagonal Boron Nitride Atomic Monolayer by Controlling Nucleation Seeds and Domains.

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