High-performance electrolytic oxygen evolution with a seamless armor core-shell FeCoNi oxynitride.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrocatalysts are crucial for water oxidation in energy conversion and storage.
• Developing active, low-cost, and durable catalysts remains a significant challenge.

Purpose of the Study:

• To synthesize and characterize a novel nitride-core, oxide-shell structured FeCoNi oxynitride electrocatalyst.
• To evaluate its efficiency for the oxygen evolution reaction (OER).

Main Methods:

• Synthesis of FeCoNi oxynitride with a specific core-shell structure.
• Electrochemical testing in alkaline media (1 M KOH).
• Density functional theory (DFT) simulations to understand reaction mechanisms.

Main Results:

• The FeCoNi oxynitride catalyst achieved a current density of 10 mA cm-2 at a low overpotential of 0.291 V.
• Performance exceeded commercial IrO2, RuO2, and Pt/C catalysts.
• Activity was comparable to state-of-the-art OER catalysts like NiFe-LDH and NiCo2O4.

Conclusions:

• The nitride-core, oxide-shell structure enhances catalytic activity through synergistic effects.
• FeCoNi oxynitride represents a promising new class of multimetallic oxynitrides for efficient electrolytic oxygen evolution.