A study of carbon nanotube formation by C2H2 decomposition on an iron based catalyst using a pulsed method

The synthesis of multiwalled carbon nanotubes has been studied using a pulsed catalytic method. Acetylene was used as carbon generation reactant and silica or alumina supported iron as catalysts. Different metal loadings and various reaction temperatures were evaluated. The carbon growth over the catalysts has been followed gravimetrically ‘in situ’. The reaction was stopped after different pulse numbers in an attempt to control both the diameters and the lengths of the carbon nanotubes, which were characterised by transmission electron microscopy (TEM). A consecutive step growing mechanism is used to describe our experiments.