Tailoring porosity of starch-derived biocarbon for enhanced supercapacitor performance

ABSTRACT

Carbon materials derived from biomass offer promising prospects for energy storage due to their eco-friendly nature, abundance, and distinctive porous structures. In this study, starch powder was used to synthesise activated biocarbon for supercapacitor electrodes. Spherical carbon particles with an average diameter of 250 nm were obtained using hydrothermal synthesis followed by chemical activation with KOH solution. Physical properties were analysed using scanning electron microscopy, X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, and N₂ adsorption/desorption analysis. Optimally activated biocarbon was achieved at an activation temperature of 900°C, exhibiting a specific surface area of 2730 m² g⁻¹ and an average pore size of 2.69 nm. The mesoporous structure facilitated ion movement, even at a high scan rate. The resultant symmetric supercapacitor exhibited an energy density of 60.16 Wh kg⁻¹ (@140 W kg⁻¹) and a power density of 24,590 W kg⁻¹ (@51.24 Wh kg⁻¹), surpassing commercial activated carbon.

KEYWORDS:

• Supercapacitor
• activated carbon
• biomass-derived carbon
• starch
• mesoporous

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/10667857.2024.2338628

Additional information

Funding

This research was supported by the National Research Council of Science & Technology (NST) grant from the Korean government (MSIT) (No. CAP22072-000) and the Development of high-power capacitor (supercapacitor) performance enhancement technology customised for companies by the Ministry of Trade, Industry, and Energy and the Korea Evaluation Institute of Industrial Technology [Project No: 00155725/Project Name: Development of battery capacitors for long-term, high-capacity, and high power energy storage system]