Applicable Descriptors under Weak Metal-Oxygen d-p Interaction for the Oxygen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The oxygen evolution reaction (OER) is vital for water electrolysis and renewable energy.
• Existing descriptors for OER catalytic materials lack effectiveness in ionic systems.
• Ionic interactions significantly influence catalytic activity in oxide systems.

Purpose of the Study:

• To identify effective descriptors for OER electronic structure-performance relationships in ionic systems.
• To address the limitations of current OER descriptors in oxide-based catalysts.
• To propose new composite descriptors tailored for ionic catalytic materials.

Main Methods:

• Evaluation of traditional OER descriptors (d-band center, charge transfer energy) in ionic oxide systems.
• Development and validation of novel composite descriptors for ionic catalytic materials.
• Extension of findings to multi-component and high-entropy oxides.

Main Results:

• Traditional OER descriptors are ineffective for oxide systems due to dominant ionic bonding.
• Ionic interactions significantly modulate OER catalytic activity.
• The metal d-band unoccupied states parameter and active states parameter are effective OER descriptors for ionic materials.

Conclusions:

• This study establishes effective OER descriptors for ionic catalytic systems, filling a critical knowledge gap.
• The proposed descriptors provide a new theoretical foundation for designing efficient OER catalysts.
• Findings guide the development of advanced catalysts for water electrolysis and energy conversion.