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Updated: Jul 12, 2026
09:23
Fabrication, Densification, and Replica Molding of 3D Carbon Nanotube Microstructures
Published on: July 2, 2012
A structure model and growth mechanism for multishell carbon nanotubes.
Science (New York, N.Y.)
|March 3, 1995
Summary
A new model explains the microstructure of graphite multishell nanotubes by proposing a mix of scroll-shaped and cylindrical graphene sheets. This model accounts for observed chiral angles, lattice patterns, and dome formations in these advanced carbon nanomaterials.
Area of Science:
- Materials Science
- Nanotechnology
- Solid-State Physics
Background:
- Graphite multishell nanotubes (GMNTs) exhibit complex microstructures.
- Understanding GMNT microstructure is crucial for advanced material applications.
- Previous models have not fully explained observed structural characteristics.
Purpose of the Study:
- To propose a novel model explaining the microstructure of arc-discharge-grown GMNTs.
- To reconcile theoretical models with experimental observations of GMNTs.
- To elucidate the formation mechanisms of GMNTs, including closure domes.
Main Methods:
- Development of a theoretical model based on scroll-shaped and concentric cylindrical graphene sheets.
- Analysis of the model's consistency with experimental data on chiral angles and lattice fringe patterns.
- Investigation of thermal contraction effects on the graphite lattice parameter (c).
Main Results:
- The proposed model successfully explains the limited range of chiral angles within tubules.
- It accounts for asymmetric (0002) lattice fringe patterns and singular fringe spacings.
- Anisotropic thermal contraction explains a minor increase in the c parameter, but not singular fringe spacings.
Conclusions:
- The scroll-and-cylinder graphene sheet model provides a comprehensive explanation for GMNT microstructure.
- The model elucidates the formation of multishell closure domes, initiated by fullerene domes.
- Further research may explore the implications of this model for nanotube synthesis and properties.
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