Pyrochlore-Type Bi₂Ru₂O₇ With Regulated Local Electronic Structure for Efficient Oxygen Evolution Reaction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Anion-exchange membrane water electrolysis (AEMWE) is a promising hydrogen production technology.
• Efficient and cost-effective oxygen evolution reaction (OER) electrocatalysts are crucial for AEMWE but currently limited.
• Existing catalysts like ruthenium dioxide (RuO2) face challenges in activity, stability, and cost.

Purpose of the Study:

• To develop novel electrocatalysts for OER in AEMWE.
• To investigate pyrochlore-type bismuth ruthenates (Bi2Ru2O7, BRO) as potential OER electrocatalysts.
• To compare the performance of BRO with RuO2 in terms of activity, stability, and efficiency.

Main Methods:

• Synthesis and characterization of pyrochlore-type bismuth ruthenates (BRO).
• Electrochemical evaluation of BRO for OER, including activity and stability testing.
• Assembly and testing of an AEM electrolyzer using BRO as the anode catalyst.

Main Results:

• BRO exhibits over 20 times higher OER activity compared to RuO2.
• BRO demonstrates enhanced performance with 48.3 wt.% less ruthenium content than RuO2.
• The enhanced activity of BRO is attributed to the electronic structure modulation by Bi, optimizing oxygen intermediate adsorption.
• AEM electrolyzers with BRO anodes show higher energy efficiency and improved stability over 120 hours compared to RuO2.

Conclusions:

• Pyrochlore-type bismuth ruthenates (BRO) are highly active and stable electrocatalysts for OER in AEMWE.
• BRO offers a promising alternative to RuO2, enabling more efficient and cost-effective hydrogen production.
• The study highlights the potential of tailored electronic structures in catalyst design for electrochemical applications.