| dc.description.abstract | The purpose of this study is to investigate the defects resulting from the etching and N2 doping process which have the potential to increase the surface area of carbon nanotubes (CNTs), and consequently enhance the energy density for energy storage devices. The synthesis of CNTs was carried out on an aluminium (Al) substrate followed by activation through KOH etching and controlled air oxidation at high temperatures to promote porosity. Although KOH etching yielded promising results in terms of porosity, however, the temperature used exceeded the melting point of the Al substrate. As a result, the CNT films needed to be scraped off from the substrate. The effect of oxidation of CNTs on capacitance and morphology was investigated. The results revealed an ideal oxidation time of less than 25 minutes which can increase the specific capacitance. However, longer durations may damage the CNTs and consequently reduce the capacitance. Moreover, the study compared the morphology and capacitance characteristics of CNTs synthesized using Ar and N2 as carrier gas and we found that N2 is a more cost-effective, practical, and feasible option for industrial applications. Notably, a higher gravimetric capacitance with a value of 68F/g was obtained using N2 as a carrier gas. However, further investigations are needed to determine the underlying cause of this improvement. In summary, this study highlights practical techniques for enhancing the surface area and porosity of CNTs, with and without a substrate, particularly for the development of high energy density supercapacitors. | |
