An Integrated Stainless Steel-Based Electrode for Durable Direct Natural Seawater Electrolysis.

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Direct seawater electrolysis for hydrogen production faces challenges due to catalyst deactivation and material corrosion from seawater's complex composition.
• Existing methods often require pre-treatment of seawater, increasing complexity and cost.

Purpose of the Study:

• To develop a durable and cost-effective system for direct hydrogen production from natural seawater.
• To investigate the mechanism of enhanced water dissociation and selectivity in a novel electrolyzer design.

Main Methods:

• Fabrication of a multistage structure using a stainless steel substrate with integrated platinum atomic clusters and a nickel-iron layered double hydroxide (NiFe-LDH) anticorrosive coating.
• Performance testing of the seawater electrolyzer under various current densities for extended durations (600-1000 hours).
• In situ characterization techniques to analyze interfacial water behavior and catalyst-ion interactions.

Main Results:

• The developed seawater electrolyzer demonstrated stable operation for over 1000 hours at 200 mA cm⁻² (1.78 V) and 600 hours at 400 mA cm⁻² (2.04 V).
• Achieved a cost reduction of over 40% and ultralow energy consumption of 4.26 kWh Nm⁻³ H₂.
• Revealed that Pt atomic clusters promote water dissociation by inducing dynamic transformation of interfacial water hydrogen bonds and optimizing adsorption selectivity against chloride ions.

Conclusions:

• The integrated design of catalysts, anti-corrosion coating, and porous transport layer offers an innovative and practical approach for direct seawater electrolysis.
• This method significantly enhances durability and efficiency, paving the way for cost-effective green hydrogen production from abundant seawater resources.