Dynamic rhenium dopant boosts ruthenium oxide for durable oxygen evolution

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Heteroatom-doping is a common strategy to enhance ruthenium dioxide (RuO2) performance in the acidic oxygen evolution reaction (OER).
• Conventional dopants exhibit static electron redistribution, limiting adaptive improvements in catalytic activity and stability.

Purpose of the Study:

• To investigate the dynamic electron accepting-donating behavior of Rhenium (Re) dopants in RuO2 for OER.
• To elucidate the mechanism by which dynamic doping enhances catalytic activity and stability.
• To demonstrate the potential of adaptive dopants in designing next-generation electrocatalysts.

Main Methods:

• Synthesis of Re-doped RuO2 (Re0.06Ru0.94O2).
• In situ characterizations to monitor dopant behavior during OER.
• First-principle computations to understand electronic interactions and reaction mechanisms.

Main Results:

• Re dopants exhibit dynamic electron accepting-donating behavior, unlike static conventional dopants.
• Re activates Ru sites by accepting electrons and prevents Ru dissolution by donating electrons at high potentials.
• Re0.06Ru0.94O2 shows a high mass activity (500 A g-1) and excellent stability (S-number = 4.0 × 10^6).

Conclusions:

• Dynamic electron interactions between Re and Ru facilitate the adsorbate evolution mechanism and lower adsorption energies for oxygen intermediates.
• Adaptive doping with dynamic dopants offers a promising strategy to boost the activity and stability of electrocatalysts.
• This work provides a new design principle for adaptive electrocatalysts for clean energy applications.