From hard carbon to activated carbon: influence of surface area and pore structure on the electrochemical performance of coconut rachis-derived supercapacitor electrodes
Year: 2026
Type: article
Abstract: The performance of supercapacitors depends on the structural characteristics of electrode materials and their interactions with electrolytes. In the present work, hard carbon (HC) and chemically treated coconut rachis-derived activated carbon (AC) are comparatively studied for understanding the role of porosity, surface area and electrochemical performance. Through chemical activation, the compact structure of HC was converted to a hierarchically porous AC, resulting in an increased specific surface area from 32 to ~1025 m² g⁻¹. Such AC provided rich electrochemical active sites along with efficient transport of electrolyte ions. Structural and compositional changes induced by activation were characterised using FESEM, BET, EDX, XRD, FTIR, and Raman spectroscopy. Electrochemical performances of HC and AC were analysed using different aqueous electrolytes. In all electrolytes, AC showed better capacitive behaviour than HC due to the developed hierarchical pore system and high surface area. AC in 6 M KOH showed a maximum specific capacitance of 201 F g⁻¹. Besides, the supercapacitor assembled using AC in 6 M KOH showed a high specific capacitance with ~93% capacitance retention after 2000 cycles of charge-discharge. These findings demonstrate that engineering the pore structure and surface area of biomass-derived carbon is essential for enhancing supercapacitor performance.
Source: Scientific Reports
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,690
Award: G1299797539
OpenAlex ID: W7208785904