Switchable Acidic Oxygen Evolution Mechanisms on Atomic Skin of Ruthenium Metallene Oxides

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Ruthenium dioxide (RuO2) is a promising catalyst for acidic oxygen evolution reaction (OER) due to its efficiency and low cost.
• However, RuO2 stability is limited by the lattice oxygen mechanism (LOM).

Purpose of the Study:

• To develop a stable and highly active RuO2-based catalyst for acidic OER.
• To investigate a novel metallene-based core-skin structure for tuning OER pathways.

Main Methods:

• Fabrication of metallene-based core-skin structures with varying core species (metallene oxides vs. metallenes).
• Electrochemical characterization of oxygen evolution reaction (OER) activity and stability.
• Spectroscopic analyses and theoretical calculations to elucidate reaction mechanisms.

Main Results:

• The Pd@RuO2 metallene catalyst exhibited a low overpotential of 189 mV at 10 mA cm-2 for acidic OER, outperforming PdO@RuO2 metallenes.
• The core-skin structure enabled a switch from LOM to an adsorbate evolution mechanism.
• The catalyst demonstrated robust stability with negligible decay over 100 hours at 50 mA cm-2.

Conclusions:

• The metallene-based core-skin structure effectively regulates the OER pathway and enhances catalyst performance.
• The Pd-metallene core acts as an electron donor, optimizing active site energetics and stability.
• This approach offers a new strategy for designing advanced electrocatalysts.