Interface-Growth-Assisted Molten Salt Synthesis of Cobalt-Embedded Ruthenium Oxide for Oxygen Evolution...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Ruthenium oxide (RuO2) is a potential alternative to iridium oxide (IrO2) for proton-exchange-membrane water electrolysis (PEMWE).
• Poor stability of RuO2 hinders its practical application in PEMWE.

Purpose of the Study:

• To develop a stable and efficient anode catalyst for PEMWE.
• To improve the stability and performance of RuO2-based catalysts.

Main Methods:

• Interface-growth-assisted molten salt synthesis (MSS) using a lanthanum cobaltate (LaCoO3) template.
• Preparation of cobalt (Co)-embedded RuO2 (Co-RuO2) nanorods.
• Anode catalyst evaluation in a PEMWE electrolyzer.

Main Results:

• Co-RuO2 nanorods exhibited enhanced stability, operating steadily for over 300 hours at 500 mA cm-2.
• The MSS strategy promoted anisotropic growth and exposure of active RuO2 crystal planes.
• In situ topological transformation incorporated Co into the RuO2 lattice, improving catalytic properties.

Conclusions:

• Template-directed interface growth in MSS is effective for preparing stable, anisotropic RuO2 catalysts.
• Co substitution in RuO2 stabilizes oxygen vacancies and enhances metal-oxygen covalency, improving PEMWE performance.
• The developed Co-RuO2 catalyst shows promise for practical PEMWE applications.