Selective Graphene Formation on Copper Twin Crystals

 作 者

 摘 要

Selective graphene growth on copper twin crystals by chemical vapor deposition has been achieved. Graphene ribbons can be formed only on narrow twin crystal regions with a (001) or high-index surface sandwiched between Cu crystals having (111) surfaces by tuning the growth conditions, especially by controlling the partial pressure of CH₄ in Ar/H₂ carrier gas. At a relatively low CH₄ pressure, graphene nucleation at steps on Cu (111) surfaces is suppressed, and graphene is preferentially nucleated and formed on twin crystal regions. Graphene ribbons as narrow as 100 nm have been obtained in experiments. The preferential graphene nucleation and formation seem to be caused primarily by a difference in surface-dependent adsorption energies of reactants, which has been estimated by first principles calculations. Concentrations of reactants on a Cu surface have also been analyzed by solving a diffusion equation that qualitatively explains our experimental observations of the preferential graphene nucleation. Our findings may lead to self-organizing formation of graphene nanoribbons without reliance on top-down approaches in the future.

 详细资料

• 文献种类:期刊
• 期刊名称: Journal of the American Chemical Society
• 期刊缩写: J. Am. Chem. Soc.
• 期卷页: 2012年  120718111748001页
• ISBN: 0002-7863

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