Fishnet-like double active layer-loaded carbon fiber for electrical double-layer capacitors

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• High-performance energy storage materials are crucial for meeting the increasing demand for energy storage devices.
• Developing advanced electrode materials is key to improving the efficiency and longevity of capacitors.
• Binder-free electrodes simplify device fabrication and can enhance electrochemical performance.

Purpose of the Study:

• To design and synthesize a novel binder-free electrode for symmetric capacitors.
• To investigate the structure-property relationships of iron oxide nanorods coated with an oxygen-rich carbon layer.
• To evaluate the electrochemical performance, including capacitance and cycling stability, of the developed electrode material.

Main Methods:

• Fabrication of a fishnet-like Fe2O3 nanorod@oxygen-rich carbon layer structure directly onto carbon fiber cloth.
• Utilizing oxidation treatment to introduce oxygen-containing functional groups and create active sites.
• Characterization of the electrode material's morphology, structure, and electrochemical properties.
• Testing the electrode in a symmetric capacitor configuration to assess areal specific capacitance, rate capability, and cycling stability.

Main Results:

• The optimal OC@Fe2O3-ACC sample demonstrated a high areal specific capacitance of 1687 mF cm-2 at 1 mA cm-2.
• An excellent capacity retention of 58.7% was achieved even at a high current density of 15 mA cm-2.
• The electrode exhibited remarkable long-term cycling stability, retaining 80% of its initial capacitance after 12,000 cycles.

Conclusions:

• The developed fishnet-like Fe2O3 nanorod@oxygen-rich carbon layer structure serves as an effective binder-free electrode for high-performance symmetric capacitors.
• The combination of Fe2O3 nanorods and the oxygen-rich carbon layer, along with oxidation treatment, significantly enhances electrochemical properties.
• This approach offers a promising strategy for fabricating advanced electrode materials for next-generation energy storage applications.