Efficient oxygen evolution reaction from iron-molybdenum nitride/molybdenum oxide heterostructured composites

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• The oxygen evolution reaction (OER) is crucial for energy conversion technologies.
• Developing efficient and cost-effective OER electrocatalysts remains a significant challenge.
• Integrating multiple active sites can potentially enhance catalytic performance.

Purpose of the Study:

• To synthesize and evaluate a novel iron-molybdenum nitride/molybdenum oxide composite electrocatalyst for OER.
• To investigate the synergistic effects of combining different active species for improved electrocatalytic activity.
• To provide insights into designing efficient electrocatalysts using earth-abundant metals.

Main Methods:

• Synthesis of a Fe-Mo5N6/MoO3-550 composite electrocatalyst.
• Electrochemical characterization of the catalyst's performance in OER.
• Analysis of electronic interactions between composite components to understand catalytic mechanisms.

Main Results:

• The Fe-Mo5N6/MoO3-550 composite exhibited excellent OER electrocatalytic performance.
• Achieved current densities of 10 and 20 mA cm⁻² at low overpotentials of 201 and 216 mV, respectively.
• Demonstrated superior performance compared to most previously reported electrocatalytic systems.

Conclusions:

• The composite electrocatalyst shows remarkable efficiency for the oxygen evolution reaction.
• Strong electronic interactions between Fe, Mo5N6, and MoO3 species accelerate reaction kinetics.
• This study highlights the potential of inexpensive metal-based composites for advanced electrocatalysis.