C2H2 interaction with Ni nanocrystals: towards a better understanding of carbon nanotubes nucleation in CVD synthesis.
Ultramicroscopy
; 109(5): 381-4, 2009 Apr.
Article
em En
| MEDLINE
| ID: mdl-18995966
ABSTRACT
We present a study of the early stages of carbon nanotubes nucleation in CVD synthesis by combining field ion/electron emission microscopy (FIM/FEM) and atom-probe investigation (AP) of the nickel-carbon interaction. Acetylene decomposition on Ni tips at 873K is observed to induce additional step formation on an initially facetted (polyhedral) crystal. Carbon-enriched steps are then observed to act as preferential nucleation centers of graphene sheets formation. Atom-probe experiments reveal C(2) and C(3) species and frequency dependent studies demonstrate that the origin of these species is different from C(1). Experiments provide clear evidence for the crucial role of carbon-enriched steps as nucleation sites of graphene sheets on the Ni surface.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Ultramicroscopy
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Bélgica