Sustained oxygen evolution reaction by 2D mesoporous polyoxometalate-derived composite electrocatalysts

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The oxygen evolution reaction (OER) is crucial for sustainable energy technologies like water electrolysis.
• Developing efficient, durable, and cost-effective OER electrocatalysts is essential for green hydrogen production.
• Noble metal-based catalysts are effective but expensive, driving research into alternatives.

Purpose of the Study:

• To design and synthesize a novel, noble metal-free composite electrocatalyst for the oxygen evolution reaction (OER).
• To achieve high electrical conductivity, reactivity, and durability for efficient water electrolysis.
• To demonstrate a scalable synthetic strategy for advanced electrocatalyst fabrication.

Main Methods:

• A scalable top-down fabrication approach using Keggin-type polyoxomolybdate Ni[HPMo^VI ₁₂O₄₀] as a precursor.
• Synthesis of Ni metal clusters deposited on η-MoC/MoO₂ nanocomposites.
• Anchoring the nanocomposites onto electrically conductive N, P-doped mesoporous carbon.

Main Results:

• A high-performance OER composite electrocatalyst with an overpotential of 320 mV at 10 mA/cm² (η₁₀).
• Sustained OER activity over 20 hours in 1 M KOH at a low overpotential of 360 mV.
• High faradaic efficiency (>95%) for the oxygen evolution reaction.

Conclusions:

• The developed composite catalyst offers a promising noble metal-free alternative for efficient OER.
• The novel synthetic strategy enables the creation of multifunctional metal carbide/oxide composites.
• This approach facilitates the development of advanced electrocatalysts for energy conversion and storage applications.