Publication: Synthesis of microalgae-derived activated carbon electrode for supercapacitor application
Loading...
Date
2025-08-01
Authors
Lim, Pei Fen
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The rising global energy demand and environmental concerns associated with fossil fuel use have accelerated the need for sustainable energy solutions. Renewable sources like solar and wind energy offer clean alternatives but are intermittent, requiring efficient energy storage systems. Supercapacitors, known for their high- power density and long cycle life, rely heavily on the performance of electrode materials such as activated carbon (AC). This study explores the use of microalgae waste as a sustainable precursor for activated carbon production. After acid pretreatment, the biomass was pyrolyzed into biochar and chemically activated, but the resulting AC electrodes showed low specific capacitance. Subsequently, biochar was directly used as the electrode material, but its poor conductivity limited its effectiveness. To overcome these challenges, a physical activation method using carbon dioxide was employed, resulting in physically activated carbon (PAC) with improved structural and electrochemical properties. The resulting PAC exhibited a high specific surface area of 772.38 m²/g and a pore volume of 0.38 m²/g. To further improve performance, PAC was mixed with commercial activated carbon (COAC) in two ratios (2:1 and 1:2). The 2:1 mixture which contains more PAC was selected for electrode fabrication. The optimized PAC/COAC-2:1 electrode achieved a specific capacitance of 119.81 F/g (1 mV/s), and when assembled into a pouch cell, delivered 46.92 F/g, with 57.8% retention after 350 cycles. The device reached an energy density of 7.12 Wh/kg and a power density of 440.32 W/kg. It successfully powered a fan for 2 minutes 25 seconds and lit a red LED for 15 minutes, demonstrating strong potential for sustainable, low-power energy storage applications.