Synthesis of RuO₂-Co₃O₄ Composite for Efficient Electrocatalytic Oxygen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Water splitting using renewable electricity is a promising method for sustainable hydrogen (H2) production.
• The oxygen evolution reaction (OER) is a critical bottleneck in water electrolysis due to sluggish kinetics.
• Development of efficient and cost-effective OER electrocatalysts is essential for improving overall water splitting efficiency.

Purpose of the Study:

• To synthesize and characterize efficient RuO2-Co3O4 composite electrocatalysts for the oxygen evolution reaction.
• To optimize the synthesis parameters for achieving high surface area and superior electrocatalytic activity.
• To evaluate the performance and stability of the developed composite as an OER electrocatalyst in alkaline media.

Main Methods:

• Solvothermal synthesis, ion exchange, and calcination were employed to create RuO2-Co3O4 composites.
• Optimization involved varying precursor ratios, specifically RuCl3·xH2O and Co-MOF.
• Electrocatalytic performance was assessed through measurements of overpotential, Tafel slope, and electrochemical stability.

Main Results:

• The optimal Co3O4-RuO2-10 composite (RCO-10) exhibited the largest specific surface area and best electrocatalytic performance.
• RCO-10 demonstrated a low overpotential (η10 = 272 mV) and a small Tafel slope (64.64 mV dec⁻¹).
• The composite showed excellent electrochemical stability and outperformed many existing cobalt-based oxide catalysts.

Conclusions:

• A straightforward three-step synthesis method yields highly efficient Co3O4-RuO2 composite electrocatalysts.
• The optimized RCO-10 composite offers a promising solution for high-performance electrocatalytic oxygen evolution.
• Integration with a carbon cloth substrate creates a stable, self-supporting electrode for practical applications.