Excellent frequency response of vertically aligned MWCNT electrode for EDLC

Abstract

A vertically aligned multi-walled carbon nanotube (MWCNT) electrode and a disordered MWCNT electrode are prepared to compare their structural differences and such capacitive performances as frequency response. The frequency response of a capacitor assembled with aligned MWCNT electrodes and a conventional PC-based electrolyte is much superior to a corresponding capacitor with disordered MWCNT electrodes. Such a merit of aligned MWCNT electrodes is observed even for an ionic liquid electrolyte system with high viscosity, diethylmethyl (2-methoxyethyl) ammonium tetrafluoroborate (DEMEBF4). The obtained results demonstrate that the aligned MWCNT electrode has ideal ion-accessible structure with excellent electron pathways that provide a high-rate capability regardless of electrolytes.