Growth of carbon nanotubes over Fe-Co and Ni-Co catalysts supported on different phases of TiO2 substrate by thermal CVD

The aim of this work is to examine the properties of CNTs formed on Fe-Co and Ni-Co bimetallic catalysts supported on different phases of TiO2 (anatase and rutile) by wet impregnation method. The CNTs are grown from decomposition of acetylene via Thermal CVD at 700 degrees C using the prepared catalysts. The nanomaterials were characterized by XRD, Xmap, BET, FESEM, TEM, and Raman spectroscopy. It was found that the catalyst samples supported on rutile TiO2 have higher specific surface area, smaller catalytic nanoparticles with denser distribution and very more activity compared to anatase ones. Consequently, the CNTs nucleated from nanoparticles supported on rutile TiO2 possess higher density, smaller average diameters and narrower diameter distribution compared to grown CNTs on anatase samples. Moreover, it was observed that the Fe-Co bimetallic catalysts regardless of TiO2 support phase, possesses more catalytic activity and higher average growth rate of CNTs in compare with Ni-Co catalysts.