Dynamic oxygen adsorption on single-atomic Ruthenium catalyst with high performance for acidic oxygen evolution...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Proton electrolyte membrane electrolyzers require efficient and stable electrocatalysts for the oxygen evolution reaction (OER) in acidic media.
• Developing cost-effective and sustainable catalysts is essential for advancing clean energy technologies.

Purpose of the Study:

• To develop a highly active and durable single-atom catalyst for acidic OER.
• To investigate the catalytic mechanism and stability of the proposed catalyst.

Main Methods:

• Synthesis of atomically dispersed Ru1-N4 sites on a nitrogen-carbon support (Ru-N-C).
• Electrochemical characterization of the Ru-N-C catalyst for OER performance.
• Operando synchrotron radiation X-ray absorption spectroscopy and infrared spectroscopy.
• Theoretical calculations to elucidate the catalytic mechanism.

Main Results:

• The Ru-N-C catalyst exhibited exceptional intrinsic activity with a mass activity of 3571 A gmetal−1 and a turnover frequency of 3348 O2 h−1.
• A low overpotential of 267 mV was achieved at a current density of 10 mA cm−2.
• The catalyst demonstrated excellent stability, with no significant deactivation after 30 hours of operation in an acidic environment.
• Operando spectroscopy and theoretical calculations revealed dynamic oxygen atom adsorption on the Ru site, explaining the high activity and stability.

Conclusions:

• Atomically dispersed Ru1-N4 sites on a nitrogen-carbon support represent a highly efficient and durable electrocatalyst for acidic OER.
• The catalyst's performance is attributed to the unique O-Ru1-N4 active site and its dynamic oxygen adsorption behavior.
• This advancement holds significant promise for cost-effective and sustainable energy supply in proton electrolyte membrane electrolyzers.