Electrophoretic deposition of cobalt catalyst layer over stainless steel for the high yield synthesis of carbon nanotubes

Electrophoretic deposition was carried out to prepare cobalt catalyst layer over stainless steel for the growth of multi-walled carbon nanotubes (MWCNTs) via chemical vapour deposition. The effects of temperatures (700, 800 and 900 °C) and gas ratio of hydrogen to acetylene (0:50, 25:25 and 40:10 sccm) on the growth of carbon nanotubes (CNTs) were investigated. The morphology and crystalline nature of the purified CNTs were examined with scanning and transmission electron microscopy, and Raman spectroscopy. MWCNTs with high yield was grown on cobalt coated stainless steel at 700 °C, using hydrogen to acetylene gas ratio of 25:25 sccm. Electrophoretic deposition was demonstrated to be a simple technique for the catalyst preparation, which in turn makes the growth of CNTs economical and scalable.