The effect of the combustible agents on the synthesis of Fe–Mo/MgO catalysts for the production of carbon nanotubes

The production of Fe–Mo/MgO by Solution Combustion Synthesis (SCS) for use as catalysts in single‐walled carbon nanotube (SWNT) synthesis was evaluated. Glycine, urea, citric acid and polyethylene glycol 200 and 400 were tested as combustible agents (CA). Iron and magnesium nitrates and ammonium molybdate were used as catalyst precursors. Four different proportion ratios of combustible/metals salts were tested. The addition of CA greatly effects the morphology and density of the produced catalyst. Carbon nanotubes were evaluated using thermogravimetric analysis, Raman spectroscopy, scanning and transmission electron microscopes and by measuring the electrical conductivity of the carbon nanotubes dispersed in chloroform. The highest absolute carbon yield was obtained with the urea, but carbon nanotubes with higher G/D ratios were produced with glycine as the CA. However, the higher yield of carbon per volume of catalyst was produced using polyethylene glycol. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)