Growth of Adlayer Graphene on Cu Studied by Carbon Isotope Labeling
2013; American Chemical Society; Volume: 13; Issue: 2 Linguagem: Inglês
10.1021/nl303879k
ISSN1530-6992
AutoresQiongyu Li, Harry Chou, Jin‐Hui Zhong, Jun-Yang Liu, Andrei Dolocan, Junyan Zhang, Yinghui Zhou, Rodney S. Ruoff, Shanshan Chen, Weiwei Cai,
Tópico(s)Diamond and Carbon-based Materials Research
ResumoThe growth of bilayer and multilayer graphene on copper foils was studied by isotopic labeling of the methane precursor. Isotope-labeled graphene films were characterized by micro-Raman mapping and time-of-flight secondary ion mass spectrometry. Our investigation shows that during growth at high temperature, the adlayers formed simultaneously and beneath the top, continuous layer of graphene and the Cu substrate. Additionally, the adlayers share the same nucleation center and all adlayers nucleating in one place have the same edge termination. These results suggest that adlayer growth proceeds by catalytic decomposition of methane (or CH(x), x < 4) trapped in a "nano-chemical vapor deposition" chamber between the first layer and the substrate. On the basis of these results, submillimeter bilayer graphene was synthesized by applying a much lower growth rate.
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