Interfacial La Diffusion in the CeO₂/LaFeO₃ Hybrid for Enhanced Oxygen Evolution Activity.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The electrochemical oxygen evolution reaction (OER) is crucial for energy storage and conversion.
• Hybrid electrocatalysts offer enhanced activity, but mechanisms are not fully understood.
• Interfacial elemental redistribution in hybrids is an under-explored area.

Purpose of the Study:

• To develop a novel CeO2/LaFeO3 hybrid electrocatalyst for improved OER performance.
• To investigate the role of interfacial elemental redistribution in enhancing OER activity.
• To elucidate the mechanism behind the enhanced electrocatalytic activity.

Main Methods:

• Synthesis of CeO2/LaFeO3 hybrid electrocatalyst.
• Electron energy loss spectroscopy (EELS) for elemental analysis.
• Elemental mapping to study interfacial cation diffusion.
• Electrochemical testing for OER activity evaluation.

Main Results:

• Demonstrated selective interfacial La diffusion from LaFeO3 to CeO2.
• Observed increased oxygen vacancies and high-valent Fe species at the interface.
• The CeO2/LaFeO3 hybrid exhibited enhanced OER activity.
• Correlated interfacial La diffusion with improved OER performance.

Conclusions:

• Interfacial cation redistribution is a key mechanism for enhancing OER activity in hybrid electrocatalysts.
• The CeO2/LaFeO3 system provides a new avenue for designing efficient OER catalysts.
• The findings offer insights applicable to other hybrid material systems.