Nanocatalyst shape and composition during nucleation of single-walled carbon nanotubes.

ABSTRACT: The dynamic evolution of nanocatalyst particle shape and carbon composition during the initial stages of single-walled carbon nanotube growth by chemical vapor deposition synthesis is investigated. Classical reactive and ab initio molecular dynamics simulations are used, along with environmental transmission electron microscope video imaging analyses. A clear migration of carbon is detected from the nanocatalyst/substrate interface, leading to a carbon gradient showing enrichment of the nanocatalyst layers in the immediate vicinity of the contact layer. However, as the metal nanocatalyst particle becomes saturated with carbon, a dynamic equilibrium is established, with carbon precipitating on the surface and nucleating a carbon cap that is the precursor of nanotube growth. A carbon

SUBMITTER: Gomez-Ballesteros JL 

PROVIDER: S-EPMC4759658 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature