Crystallographic order in multi-walled carbon nanotubes synthesized in the presence of nitrogen.
Multi-walled carbon nanotubes were synthesized by chemical vapor deposition from pure toluene and toluene/diazine mixtures using ferrocene as a catalyst precursor at 760 degrees C. As recently announced, characterization of the resulting nanotube films showed that, unlike pure carbon nanotubes, those grown in the presence of nitrogen have an extremely high degree of internal order, both in terms of the uniform chirality in the nanotube walls and of the crystallographic register between them. Here, the structure, defects, and morphology of the nanotubes were analyzed in depth using advanced electron microscopy techniques, and compared with existing models and observations. Nitrogen, which seems to be responsible for the dramatic structural order, was found to segregate preferentially within the core of the nanotubes.
Ducati
Caterina
C
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ, UK. cd251@cam.ac.uk
Koziol
Krzystof
K
Friedrichs
Steffi
S
Yates
Timothy J V
TJ
Shaffer
Milo S
MS
Midgley
Paul A
PA
Windle
Alan H
AH
D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D009584:Nitrogen / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
D046911:Macromolecular Substances; D037742:Nanotubes, Carbon; D009584:Nitrogen