Effect of different electric field parameters on produced activated carbon for supercapacitor electrode materials

Abstract

Supercapacitors have become one of the popular devices in the field of energy storage, thanks to their high power densities, fast charging, and discharging capabilities, and long cycle life. Supercapacitors can achieve both high energy and power density through the use of efficient electrode materials which have a significant impact on their performance. In this study, for the first time, in order to improve the electrochemical properties of the electrodes, we applied an electric field to the biomass-based activated carbon obtained by activation-carbonization. We also examined the effect of applied electric field strength and duration on the electrochemical properties of the electrodes by preparing five different materials. The properties of the produced materials were tested by different chemical characterization and electrochemical methods. Thanks to the electrical activation, the material’s surface area, pore volume, and pore diameters were increased, the capacitance value has increased to 295 F/g, which was 89 F/g as a result of activation–carbonization. The EFQ-4 supercapacitor has a maximum energy density of 20.49 Wh kg⁻¹ at a power density of 526.28 W kg⁻¹, and the energy density value is far superior to the energy densities of the supercapacitors located on the Ragone plane. In addition, the electric field made the material more stable, improved the cycle life, and increased the stability from 92.10 to 95.50%. The electrochemical results of the produced electrodes are promising in the field of energy storage.