Graphite-type activated carbon from coconut shell: a natural source for eco-friendly non-volatile storage devices

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Biomass-derived activated carbon is a promising electrode material for supercapacitors due to its sustainability and unique properties.
• Coconut shells offer an abundant and eco-friendly source for activated carbon production.
• Supercapacitors are crucial energy storage devices, and enhancing their performance is an active research area.

Purpose of the Study:

• To investigate the potential of activated carbon derived from coconut shells as an active material for eco-friendly supercapacitors.
• To correlate the structural and morphological properties of activated carbon with its electrochemical energy storage performance.
• To achieve high energy and power density in supercapacitors using biomass-derived materials.

Main Methods:

• Activated carbon was prepared from coconut shells using a simple steam activation process.
• Characterization techniques included X-ray diffraction (XRD), Raman spectroscopy, SEM, N2 sorption, and TGA-MS.
• Electrochemical performance was evaluated using cyclic voltammetry and galvanostatic charge-discharge in aqueous and ionic liquid electrolytes.

Main Results:

• The activated carbon exhibited a graphitic phase, high surface area (1998 m² g⁻¹), and large pore volume.
• Specific capacitance reached 132.3 F g⁻¹ in aqueous electrolyte and an outstanding 219.4 F g⁻¹ in ionic liquid (MPPyFSI).
• Supercapacitors demonstrated high specific energy (92.1 W h kg⁻¹) and power density (2046.9 W kg⁻¹), maintaining performance at high current densities.

Conclusions:

• Activated carbon from coconut shells is a highly effective electrode material for advanced supercapacitors.
• The material's properties enable superior energy and power storage capabilities, particularly in ionic liquid electrolytes.
• This research presents a sustainable pathway for high-performance energy storage devices using abundant biomass resources.