Integrated N-Co/Carbon Nanofiber Cathode for Highly Efficient Zinc-Air Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Binder-free electrodes are crucial for reducing resistance in energy storage devices.
• Polymer binders in traditional electrodes can increase charge-transfer and ohmic resistance.
• Developing efficient, self-standing electrodes is key for advanced batteries.

Purpose of the Study:

• To create self-standing, binder-free porous cathodes for zinc-air batteries.
• To investigate the structure-property relationship of N-Co carbon nanofiber (N-Co/CNF) electrodes.
• To evaluate the electrocatalytic performance of N-Co/CNF for oxygen reduction reactions.

Main Methods:

• In situ electrospinning followed by plasma-etching to synthesize N-Co/CNF cathodes.
• Characterization techniques to analyze electrode morphology and composition.
• Electrochemical testing to assess performance in zinc-air batteries.

Main Results:

• The N-Co/CNF cathodes exhibit a multilayered carbon nanofiber structure with a novel CoN compound.
• The N-Co/CNF-300-10 cathode shows high electrocatalytic activity for oxygen reduction, with onset potential 0.995 V and half-wave potential 0.853 V.
• The electrode achieved a maximum discharge power density of 229 mW cm⁻² and a specific capacity of 659.6 mA h gZn⁻¹ in zinc-air batteries.

Conclusions:

• The developed self-standing, binder-free N-Co/CNF cathodes offer superior performance for zinc-air batteries.
• Plasma-etching effectively introduces N-doping and defects, enhancing catalytic activity.
• This method provides a viable route for fabricating high-performance electrodes for rechargeable metal-air batteries.