Partially selenized FeCo layered double hydroxide as bifunctional electrocatalyst for efficient and stable alkaline...

Area of Science:

• Electrochemistry
• Materials Science
• Sustainable Energy

Background:

• Seawater electrolysis offers a sustainable route for hydrogen production.
• Chloride ions in seawater degrade electrocatalysts, hindering practical application.
• Developing robust catalysts is crucial for efficient seawater splitting.

Purpose of the Study:

• To synthesize and evaluate a partially selenized FeCo layered double hydroxide (Se-FeCo-LDH) catalyst for seawater electrolysis.
• To investigate the catalyst's performance, durability, and mechanism in mitigating chloride ion corrosion.
• To advance clean hydrogen production technologies using abundant seawater resources.

Main Methods:

• Synthesis of partially selenized FeCo layered double hydroxide (Se-FeCo-LDH).
• Electrochemical characterization of the catalyst in alkaline and seawater electrolytes.
• Evaluation of catalytic performance for oxygen evolution reaction (OER) and overall water splitting.
• Long-term stability testing to assess durability.

Main Results:

• The Se-FeCo-LDH catalyst exhibits excellent electrocatalytic activity with a low overpotential of 229 mV at 100 mA cm⁻² for OER in 1 M KOH.
• Achieved low voltages of 1.446 V and 1.491 V for 10 mA cm⁻² in alkaline and seawater splitting, respectively.
• Demonstrated remarkable long-term stability of up to 245 hours in alkaline seawater splitting, attributed to an anion aggregation layer preventing erosion.

Conclusions:

• Partially selenized FeCo-LDH is a highly effective and durable catalyst for seawater electrolysis.
• The catalyst's unique structure protects against chloride ion damage, enabling efficient hydrogen production.
• This development provides a promising pathway for scalable clean hydrogen generation from seawater.