Cross-Doped Ru-Co Oxides with "Superaerophobic" Surfaces for Highly Efficient and Robust Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Sluggish kinetics and gas bubble adhesion hinder electrocatalyst performance in alkaline water electrolysis.
• Efficient electrocatalysts are crucial for large-scale hydrogen production.

Purpose of the Study:

• To develop a novel Ru-Co oxide composite with enhanced catalytic activity for water electrolysis.
• To investigate the mechanisms behind the improved performance.

Main Methods:

• Facile synthesis of cross-doped heteroatom Ru-Co oxide composites.
• Electrochemical characterization including overpotential measurements for HER and OER.
• In situ gas bubble analysis and theoretical calculations (DFT).

Main Results:

• Achieved low overpotentials: 11.25 mV for HER and 193.94 mV for OER at 10 mA cm⁻².
• Demonstrated stable operation at 1000 mA cm⁻² for 960 hours in an alkaline electrolyzer.
• Identified a built-in electric field (BEF) from cross-doping accelerating charge transport.
• Superaerophobic surfaces facilitated gas bubble detachment and mitigated mass transport limitations.

Conclusions:

• The cross-doping strategy in Ru-Co oxides significantly enhances electrocatalytic activity and stability for water electrolysis.
• The combination of accelerated charge transport and improved gas management offers a promising approach for designing high-performance electrocatalysts.
• This method is applicable to other Ru-based bimetal oxides for scalable hydrogen production.