Highly Stable Bifunctional Electrocatalyst Based on Carbon-Supported CoFe₂O₄/CeO₂ Heterostructure Enabled for...

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• Precious metal catalysts are expensive and unstable for water electrolysis.
• Developing efficient, non-precious metal bifunctional electrocatalysts is crucial for sustainable hydrogen production.

Purpose of the Study:

• To design and synthesize a novel heterointerfacial cobalt-iron oxide/cerium oxide composite anchored on carbon (CoFe2O4/CeO2@C).
• To evaluate its bifunctional electrocatalytic activity for overall water splitting.

Main Methods:

• Facile hydrothermal-pyrolysis approach for catalyst synthesis.
• Electrochemical characterization including overpotential measurements for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).
• Structural and electronic analyses to understand performance mechanisms.

Main Results:

• The optimized CoFe2O4/CeO2@C catalyst achieved low overpotentials (243 mV for OER, 82 mV for HER) at 10 mA cm-2 in 1 M KOH.
• It required only 1.57 V for overall water splitting, outperforming RuO2 and Pt/C benchmarks.
• The catalyst showed excellent stability with only 6.1% current density decay after 24 hours and high Faradaic efficiency.

Conclusions:

• The heterointerface in CoFe2O4/CeO2@C optimizes electronic properties for enhanced bifunctional electrocatalysis.
• This study presents a scalable strategy for developing non-precious metal catalysts for efficient water splitting.
• The developed catalyst is a promising candidate for sustainable hydrogen production.