Multiwalled carbon nanotubes catalytically grown from amorphous silica films deposited by combustion CVD

Homogeneous mixtures containing iron oxide and amorphous SiO2 were obtained through the co-deposition of these oxides via combustion chemical vapor deposition technique (CCVD). This technique allows the deposition of thin films with low-cost precursors and equipments. After deposition, the deposited samples were submitted to a heat treatment in an atmosphere composed of natural gas and H-2 at 1000 degrees C, in order to promote the growth of carbon nanotubes. Multiwalled carbon nanotubes, with diameters smaller than 15 nm, were obtained.