Strong Interfacial Electronic Coupling in Ni₃Mo₃C@MoO₂ for Durable Oxygen Evolution Reaction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The oxygen evolution reaction (OER) is crucial for electrochemical hydrogen production but suffers from slow kinetics and catalyst instability.
• Carbide/oxide heterostructures offer promising catalytic properties for OER due to unique interfacial effects.

Purpose of the Study:

• To develop high-performance OER catalysts by engineering interfacial electronic coupling between carbides and electronegative oxide nanoparticles.
• To investigate the catalytic mechanism and performance of Ni₃Mo₃C anchored on MoO₂ nanoparticles for OER.

Main Methods:

• Synthesis of Ni₃Mo₃C@MoO₂-CN catalyst with strong carbide/oxide interfacial electronic coupling.
• Electrochemical characterization of OER performance, including overpotential and durability tests.
• Analysis of interfacial electronic coupling and its effect on OER mechanism via electron transfer studies.

Main Results:

• The Ni₃Mo₃C@MoO₂-CN catalyst demonstrated excellent OER performance with a low overpotential of 197 mV at 10 mA cm⁻².
• An electrolyzer using this catalyst achieved a low cell voltage of 1.92 V at 500 mA cm⁻² with 2000 hours of stability.
• Carbide/oxide interfacial electronic coupling facilitated electron transfer, optimizing O* adsorption and promoting spontaneous OOH* formation.

Conclusions:

• Strong carbide/oxide interfacial electronic coupling is an effective strategy for designing high-performance OER catalysts.
• The Ni₃Mo₃C@MoO₂-CN catalyst shows significant potential for efficient and durable electrochemical hydrogen production.
• Understanding interfacial electronic coupling provides fundamental insights for advancing OER catalysis.