Immersion-Driven Structural Evolution of NiFeS Nanosheets for Efficient Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing cost-effective, highly active, and stable electrocatalysts is essential for water splitting to address energy and environmental challenges.
• Electrocatalytic water splitting offers a sustainable route for hydrogen fuel production.

Purpose of the Study:

• To synthesize a novel NiFeS nanosheet catalyst using a simple "immersion-sulfurization" strategy.
• To evaluate the electrocatalytic performance of the NiFeS catalyst for water splitting applications.

Main Methods:

• A two-step "immersion-sulfurization" method was employed to prepare NiFeS nanosheets directly on a NiFe foam substrate.
• Electrochemical techniques were used to assess the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) activities and stability.

Main Results:

• The synthesized NiFeS/NFF-300 catalyst exhibited efficient electrocatalytic activity for water splitting.
• An overpotential of 230 mV was required for OER at 10 mA cm⁻², with excellent stability over 24 hours.
• The catalyst demonstrated significant HER performance compared to NiFeC₂O₄/NFF and NiFe foam.

Conclusions:

• The NiFeS nanosheet structure, along with the presence of Ni ions on the surface, contributes to its superior electrocatalytic activity.
• The developed self-supported electrode offers a promising, low-cost, and scalable solution for efficient electrocatalytic water splitting.