Advanced Nickel-Based Gas Diffusion Anode for Zero-Gap Anion-Exchange Membrane Water Electrolyzers

Area of Science:

• Electrochemistry
• Materials Science
• Sustainable Energy

Background:

• Anion-exchange membrane water electrolyzers (AEMWE) are crucial for sustainable green hydrogen production.
• Reducing electrical losses and costs in AEMWEs is essential for widespread adoption.
• Current AEMWE designs face challenges with anode catalyst utilization and membrane integrity.

Purpose of the Study:

• To reduce electrical losses in AEMWEs by designing an improved anode catalyst layer.
• To enhance the performance and cost-effectiveness of green hydrogen technology.
• To investigate a novel anode modification for improved oxygen evolution reaction (OER) efficiency.

Main Methods:

• Modified nickel foam using a microporous nickel ink to create a smoother anode surface.
• Utilized mesoporous NiO (mesoNiO) catalyst integrated with a nickel powder layer for enhanced OER.
• Optimized catalyst mass loading for balanced membrane contact, reduced kinetic losses, and efficient ionic transport.

Main Results:

• Achieved a competitive current density of 2.6 A cm^-2 at 2 V cell voltage.
• Demonstrated comparable performance to state-of-the-art proton-exchange membrane water electrolyzers.
• Successfully prevented membrane punctures during assembly through anode surface smoothing.

Conclusions:

• The developed anode catalyst layer significantly reduces electrical losses in AEMWEs.
• Fluorocarbon membrane-free, zero-gap AEMWEs with platinum-free anodes show great potential for green hydrogen.
• This advancement paves the way for further research into catalyst-free water electrolyzers for future sustainable hydrogen production.