Efficient and durable seawater electrolysis with a V₂O₃-protected catalyst.

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• The ocean represents a vast resource for hydrogen production, but harsh seawater conditions impede efficient electrocatalyst performance.
• Developing robust electrocatalysts is crucial for sustainable hydrogen generation and water development.

Purpose of the Study:

• To engineer a high-performance electrocatalyst for hydrogen production in seawater.
• To investigate a protective V2O3 layer for enhanced catalyst stability and activity.
• To demonstrate the efficacy of the V2O3-protected catalyst in anion exchange membrane water electrolyzers (AEMWE).

Main Methods:

• Incorporation of a V2O3 protective layer onto low-loaded Pt and Ni3N dual-active sites.
• Electrocatalytic performance testing in simulated seawater.
• Durability assessment over 500 hours.
• Assembly and testing of anion exchange membrane water electrolyzers (AEMWE).
• In situ localized pH analysis to elucidate the protective mechanism.

Main Results:

• The V2O3-protected catalyst achieved an ultralow overpotential (80 mV at 500 mA cm-2) and significantly enhanced mass activity (30.86 times higher than Pt-C).
• Exceptional stability was demonstrated, maintaining performance for over 500 hours in seawater.
• The assembled AEMWE exhibited superior activity and durability under demanding industrial conditions.
• The V2O3 layer effectively regulated the microcatalytic environment by sequestering OH- ions and mitigating corrosion and precipitation.

Conclusions:

• The V2O3 protective layer strategy is a promising approach for stabilizing electrocatalysts in harsh seawater environments.
• This method facilitates cost-effective, large-scale green hydrogen production.
• The V2O3 layer's Lewis acid properties are key to its protective and performance-enhancing functions.