Boosting PEMWE Performance Via the Local Electronic Regulation of Ir_0.5Ru_0.5/NbN Catalyst With Synergistic Vacancy...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Proton exchange membrane water electrolysis (PEMWE) is crucial for green hydrogen production.
• Reducing reliance on precious metals like iridium is essential for cost-effective PEMWE.

Purpose of the Study:

• To develop a highly active and stable catalyst for the oxygen evolution reaction (OER) in acidic media.
• To investigate the role of defect engineering and strong metal-support interaction (SMSI) in enhancing catalyst performance.
• To reduce iridium loading in PEMWE systems.

Main Methods:

• Synthesis of Ir0.5Ru0.5 nanoclusters supported on nitrogen-vacation-rich niobium nitride (NbN).
• Defect engineering and doping strategies to modulate electronic properties of active sites.
• Electrochemical characterization of OER activity and stability.
• Performance evaluation as an anode in a PEMWE cell.

Main Results:

• The Ir0.5Ru0.5/NbN catalyst achieved a low OER overpotential of 228 mV at 10 mA cm-2.
• Exceptional stability was demonstrated, with no degradation after 700 hours of operation.
• The catalyst exhibited outstanding performance in PEMWE, with a cell voltage of 1.79 V at 2 A cm-2.
• Defect engineering successfully enhanced SMSI and accelerated OER kinetics.

Conclusions:

• The developed Ir0.5Ru0.5/NbN catalyst offers a viable and efficient approach for low-iridium loading in PEMWE.
• This strategy presents a promising pathway for cost-effective green hydrogen generation.
• The study highlights the importance of defect engineering for advanced electrocatalyst design.