Biomass-Derived Activated Porous Carbon from Foxtail Millet Husk to Utilizing High-Performance Symmetric...

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Biomass-derived carbons are sustainable alternatives for energy storage.
• Foxtail millet husk is an abundant agricultural waste with potential for valorization.
• Developing efficient electrode materials is crucial for advanced supercapacitors.

Purpose of the Study:

• To synthesize and characterize foxtail millet carbon-activated (FMCA) materials from foxtail millet husk (FMH).
• To evaluate the electrochemical performance of FMCA as electrode material in supercapacitors.
• To demonstrate the potential of FMCA for efficient energy storage applications.

Main Methods:

• Two-step synthesis involving pre-carbonization of FMH, chemical activation with KOH, and subsequent carbonization at 800 °C.
• Structural characterization using X-ray Diffraction (XRD) and Raman spectroscopy.
• Electrochemical performance evaluation in symmetric supercapacitor devices, including charge-discharge cycling and capacitance measurements.

Main Results:

• XRD confirmed the presence of graphitic structures in FMCA.
• Raman analysis indicated enhanced graphitic ordering with an I_G/I_D ratio of 1.13.
• FMCA//FMCA symmetric devices achieved a specific capacitance of 82.94 F/g at 0.5 A/g and retained 94.89% capacity over 5000 cycles.

Conclusions:

• The synthesized FMCA material exhibits excellent structural properties and electrochemical performance.
• FMCA is a promising, sustainable electrode material for high-performance electrochemical double-layer capacitors (EDLCs).
• This study highlights the potential of agricultural waste like foxtail millet husk for next-generation energy storage solutions.