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Updated: Jul 2, 2025
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
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Stabilizing Highly Active Ru Sites by Electron Reservoir in Acidic Oxygen Evolution
Jiayan Wu1, Zhongjie Qiu1, Jiaxi Zhang1
1Guangdong Provincial Key Laboratory of Fuel Cell Technology, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China.
Molecules (Basel, Switzerland)
|February 24, 2024
Summary
This study stabilizes ruthenium dioxide (RuO2) catalysts for oxygen evolution reactions by incorporating high-valence metals. Rhenium (Re) doping enhances activity and durability, offering a cost-effective solution for water electrolysis.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- Proton exchange membrane water electrolysis is limited by the slow oxygen evolution reaction (OER) kinetics.
- Ruthenium dioxide (RuO2) is a potential anode catalyst alternative to iridium dioxide (IrO2) due to its activity and lower cost.
- RuO2 dissolution under acidic OER conditions compromises its long-term stability.
Purpose of the Study:
- To develop a strategy for stabilizing RuO2 in acidic OER by incorporating high-valence metals.
- To investigate the effect of ionic electronegativity of dopants on RuO2 stability and OER performance.
- To enhance the activity and durability of RuO2-based catalysts for efficient water electrolysis.
Main Methods:
- Synthesis of high-valence metal-substituted RuO2 using a molten salt method.
- Electrochemical characterization to evaluate OER activity and stability.
- Surface analysis to determine the ratio of Ru4+/Ru3+ species and understand the role of dopants.
Main Results:
- High surface Ru4+ content positively correlates with intrinsic OER activity.
- A linear relationship exists between Ru4+/Ru3+ ratio and dopant ionic electronegativity.
- Rhenium (Re)-doped Re0.1Ru0.9O2 exhibited low overpotential (199 mV at 10 mA cm-2) and exceptional stability (>300 h at 10 mA cm-2, >25 h at 100 mA cm-2).
Conclusions:
- Incorporating high-valence metals, particularly Re, effectively stabilizes RuO2 for acidic OER.
- Re acts as an electron reservoir, mitigating Ru overoxidation and enhancing catalyst durability.
- This work presents a viable strategy for stabilizing cost-effective Ru-based catalysts for acidic OER applications.
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