A vanadium-containing high entropy alloy electrocatalyst with boosted electrocatalytic activity for oxygen evolution...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrocatalytic water splitting is crucial for green hydrogen production, but limited by sluggish oxygen evolution reaction (OER) kinetics.
• High entropy alloys (HEAs) offer tunable compositions for enhanced OER electrocatalytic activity.
• Developing efficient and cost-effective OER catalysts remains a significant challenge in renewable energy technologies.

Purpose of the Study:

• To develop a facile method for preparing a V-containing high entropy alloy catalyst.
• To investigate the role of Vanadium (V) in enhancing the electrocatalytic activity for OER.
• To explore the potential of metal-organic frameworks (MOFs) as precursors for HEA electrocatalysts.

Main Methods:

• Synthesis of a V-containing high entropy alloy catalyst (ZnCoNiFeV-MOF-900) using a flower-like MOF precursor.
• Electrochemical characterization of the catalyst's performance in oxygen evolution reaction (OER).
• Analysis of the catalyst's electronic structure and morphology to understand the role of V.

Main Results:

• The synthesized ZnCoNiFeV-MOF-900 catalyst exhibits a flower-like morphology, facilitating mass transport and active site exposure.
• Introduction of V into the high entropy alloy regulates the electronic structure and forms high-valent Ni centers, lowering the OER reaction barrier.
• The catalyst achieved a low overpotential of 284 mV at 10 mA cm⁻² for OER, demonstrating high catalytic activity.

Conclusions:

• A facile synthesis route using MOF precursors enables the preparation of high-performance V-containing HEA electrocatalysts.
• Vanadium plays a key role in optimizing the electronic structure and enhancing OER activity.
• This work provides a novel strategy for designing advanced HEA electrocatalysts for efficient energy conversion and storage applications.