Enhanced oxygen evolution over dual corner-shared cobalt tetrahedra.

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Oxygen evolution reaction (OER) is a critical but sluggish process in electrochemical applications.
• Efficient catalysts are needed to overcome OER kinetics for processes like hydrogen generation.

Purpose of the Study:

• To investigate the catalytic activity of cobalt tetrahedra stabilized on YBaCo4O7 for the oxygen evolution reaction.
• To understand the structural resilience and active sites responsible for efficient OER catalysis.

Main Methods:

• Synthesis and characterization of Swedenborgite-type YBaCo4O7 material.
• Electrochemical testing of YBaCo4O7 for oxygen evolution reaction (OER).
• Density functional theory (DFT) calculations to elucidate active sites and reaction mechanisms.

Main Results:

• YBaCo4O7 exhibits strong resilience against structural amorphization during OER.
• The material's bulk structure of corner-sharing CoO4 tetrahedra accommodates oxygen insertion and mediates stress.
• DFT calculations identified binuclear active sites of dual corner-shared cobalt tetrahedra (coordination switching 3-4) as key OER catalysts.

Conclusions:

• Cobalt tetrahedra on YBaCo4O7 are highly effective OER catalysts.
• The unique structural flexibility of YBaCo4O7 contributes to its catalytic stability and efficiency.
• The identified dual corner-shared cobalt tetrahedra motif offers a new avenue for designing advanced OER catalysts.