Alumina and silica supported metal catalysts for the production of carbon nanotubes

Catalytic activity of iron, cobalt and a mixture of iron and cobalt supported on Al2O3 and SiO2 has been investigated in the production of carbon nanotubes (NTs). The supports are obtained from different methods. Acetylene was used as the source of carbon and nitrogen as the carrier gas. The pyrolysis of hydrocarbon was carried out at 500, 600 and 700 degreesC. The effect of other reaction parameters such as rate of flow of the hydrocarbon. carrier gas and the reaction time has also been investigated. Transmission electron microscope (TEM) was used to follow the quality and nature of NTs formed. It was observed that a good quality and quantity of multiwall carbon nanotubes (MWNTs) were produced when alumina prepared from aluminum isopropoxide and deposited with a mixture of iron and cobalt catalysts was used. (C) 2002 Elsevier Science B.V. All rights reserved.