Electrochemical properties of arc-black and carbon nano-balloon as electrochemical capacitor electrodes

In this study, we used two types of carbon nanomaterials, arc-black (AcB) which has an amorphous structure and carbon nano-balloon (CNB) which has a graphitic structure as electrochemical capacitor electrodes. We made a coin electrode from these carbon materials and fabricated an electric double-layer capacitor (EDLC) that sandwiches a separator between the coin electrodes. On the other hand, RuO2 was loaded on these carbon materials, and we fabricated a pseudo-capacitor that has an ion insertion mechanism into RuO2. For comparison with these carbon materials, activated carbon (AC) was also used for a capacitor electrode. The electrochemical properties of all the capacitors were evaluated in 1M H2SO4 aqueous solution. As a result of EDLC performance, AcB electrode had a higher specific capacitance than AC electrode at a high scan rate (≥ 100 mV/s). In the evaluation of pseudo-capacitor performance, RuO2-loaded CNB electrode showed a high specific capacitance of 734 F/g per RuO2 weight.