Grain Boundary-Driven Synergistic Dual-Mechanism Catalysis in RuO₂ for Enhancing Acidic Oxygen Evolution Reaction...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Designing efficient acidic oxygen evolution reaction (OER) catalysts is crucial for sustainable hydrogen production via water electrolysis.
• Controlling defects in catalysts remains a significant challenge for improving performance.

Purpose of the Study:

• To engineer grain boundary-rich ultrathin RuO_x nanosheets (Ni,B-RuO_x) with atomic-scale defects.
• To modulate dual reaction pathways (adsorbate evolution mechanism and lattice oxygen mechanism) for enhanced OER.

Main Methods:

• Codoping RuO_x nanosheets with Nickel (Ni) and Boron (B) to create grain boundary-rich structures.
• Investigating interfacial and lattice active sites for OER pathway modulation.
• Conducting electrochemical analyses and kinetic studies in acidic media and proton exchange membrane electrolyzers.

Main Results:

• Ni,B-RuO_x exhibits exceptional catalytic activity with a low overpotential (206.8 ± 1.3 mV at 10 mA cm^-2).
• The catalyst demonstrates long-term stability exceeding 700 hours in 0.5 M H₂SO₄.
• Grain boundary engineering sustains robust interfacial reactions under harsh conditions.

Conclusions:

• The grain boundary-rich structure with dual active sites provides a new paradigm for designing highly stable acidic OER catalysts.
• This approach advances the practical application of green hydrogen production technologies.
• Atomic interface engineering is key to developing next-generation catalysts for water electrolysis.