  Addition of only 1% of acetylene into ethanol was found to enhance the growth
rate of singlewalled carbon nanotubes (SWNTs) by up to ten times. Since
acetylene is a byproduct of the thermal decomposition of ethanol, this suggests
an alternative fast reaction pathway to the formation of SWNTs from ethanol via
byproducts of decomposition. This accelerated growth, however, only occurred in
the presence of ethanol, whereas pure acetylene at the same partial pressure
resulted in negligible growth and quickly deactivated the catalyst. The dormant
catalyst could be revived by reintroduction of ethanol, indicating that
catalyst deactivation is divided into reversible and irreversible stages.
