Simultaneous Interface Engineering and Phase Tuning of CeO₂-Decorated Catalysts for Boosted Oxygen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Heterogeneous catalysts show promise for oxygen evolution reaction (OER) but face synthesis challenges.
• Controlling interfaces and phase composition is crucial for optimizing catalyst performance.

Purpose of the Study:

• To introduce a novel strategy for engineering heterogeneous catalysts using ceria (CeO2) decoration.
• To enhance oxygen evolution reaction (OER) performance through controlled interface and phase composition.
• To investigate the role of ceria in facilitating phase transitions from nitrides to metals.

Main Methods:

• Theoretical calculations to assess the effect of ceria on reaction free energy barriers.
• Experimental synthesis of catalysts decorated with varying amounts of rare earth oxides (ceria).
• Electrochemical testing to evaluate oxygen evolution reaction (OER) activity and overpotential.

Main Results:

• Ceria decoration was shown to reduce the free energy barrier for nitride-to-metal conversion.
• Experimental results confirmed controlled phase transitions from nitride to metal phases.
• The optimized Ni3FeN/Ni3Fe/CeO2-5% catalyst achieved a low overpotential of 249 mV at 10 mA cm-2 for OER.

Conclusions:

• Ceria decoration is an effective strategy for creating heterogeneous interfaces and controlling phase composition in catalysts.
• This approach enhances OER kinetics and promotes the formation of active catalytic sites.
• The findings offer new perspectives for designing efficient heterogeneous OER catalysts for energy conversion.