Aerosol-Assisted Chemical Vapor Deposition of Multi-Walled Carbon Nanotubes on Steel Substrates for Application in Supercapacitors †

Carbon nanotubes (CNTs) are grown on to steel substrates by aerosol-assisted chemical vapor deposition using ferrocene in ethanol as the carbon feedstock. The CNTs adopted a highly entangled morphology. Elemental analysis indicates that the main source of carbon for CNT growth is from the cyclopentadiene rings in ferrocene rather than the ethanol solvent. The CNT-coated steel substrates are evaluated for their performance as supercapacitor electrodes. The electrodes exhibit a high geometric capacitance of 3.4 mF cm−2 which is due to the high internal surface area, but a relatively low specific capacitance of 0.34 F g−1.