Nanotube deposition in a continuous arc reactor for varying arc gap and substrate temperature

The aim of this work was to study the effect of the physical parameters of the arc on substrate surface temperature and on the CNT growth there. The effects of arc gap and buffer gas flow through the anodic substrate were investigated. An optical pyrometric technique was used to determine the substrate surface temperature. It was found that carbon nanotube growth was favoured over the temperature range 3600-3700 ± 50 K and not favoured at higher temperatures of 3800-4000 ± 50 K. This indicates that CNT growth is unlikely to be due to vaporization/condensation of small molecular carbon species.