Nucleation and growth of single wall carbon nanotubes

TL;DR

This paper presents a simplified model of single wall carbon nanotube nucleation and growth, focusing on elementary defect processes and energy estimations, compatible with various tube sizes and helicities.

Contribution

It introduces a qualitative description based on elementary processes and energy calculations, offering insights into growth mechanisms of nanotubes from catalytic particles.

Findings

Growth mechanisms can be repeatedly applied for nanotube formation

Certain embryo arrangements favor growth, such as hexagonal networks

The model aligns with various nanotube sizes and helicities

Abstract

The nucleation and growth of single wall carbon nanotubes from a carbon-saturated catalytic particle surrounded by a single sheet of graphene is described qualitatively by using a very restricted number of elementary processes, namely Stone-Wales defects and carbon bi-interstitials. Energies of the different configurations are estimated by using a Tersoff energy minimization scheme. Such a description is compatible with a broad variety of size or helicity of the tubes. Several mechanisms of growth of the embryos are considered: one of them is made more favourable when the tubes embryos are arranged in an hexagonal network in the graphene plane. All the proposed mechanisms can be indefinitely repeated for the growth of the nanotubes.