Growth of carbon nanotubes on aluminium foil for supercapacitors electrodes

A new approach for the preparation of carbon nanotubes (CNTs) electrode is proposed in the present work. Multi-walled carbon nanotubes (MWCNTs) were grown by chemical vapour deposition on aluminium strips pre-plated with a nickel thin film as the catalyst. The CNTs were characterized by scanning and transmission electron microscopy, Brunauer–Emmett–Teller surface area measurement and thermogravimetric analysis. The nickel-plated aluminium foil with a layer of CNTs was further characterized for an assessment of its electrochemical behaviour as electrode for supercapacitors. The specific capacitances of the electrode, as derived from cyclic voltammetry measurement at 0.1 V s⁻¹ scan rate, was found to be 54 and 79 F g⁻¹ in aqueous and organic electrolytes, respectively, in line with the highest reported values for either activated carbon or MWCNTs electrodes. Further evidence in support of the viability of the present approach for the preparation of a CNTs electrode was obtained from electrochemical impedance spectroscopy.