Polyacrylonitrile (PAN)-based, microporous activated carbon fibers (ACFs) were investigated as electrode materials for electrochemical capacitors in KOH electrolyte solutions. PAN-ACFs were analyzed by using nitrogen adsorption data and the Dubinin-Raduskevich equation. The pore size distributions were narrow. As the micropore volume increased, the average micropore diameter decreased. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge-discharge profile analysis were used to investigate the penetrability of electrolyte ions into the carbon electrodes. The electrolyte ions in the carbon electrode with a large micropore diameter could be accessible easily even if the pore size distribution is narrow. However, the specific capacitance decreased in spite of the increase of the micropore volume.
- Impedance spectroscopy
- Specific capacitance
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering