Coupled MoO_3-@CoP heterostructure as a pH-universal electrode for hydrogen generation at a high current density

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient and cost-effective electrocatalysts for the hydrogen-evolution reaction (HER) is crucial for high-quality hydrogen production.
• Achieving high performance across a wide pH range (pH-universal) and at high current densities remains a significant challenge.

Purpose of the Study:

• To create a self-supporting electrode with a coupled hierarchical heterostructure for pH-universal HER catalysis.
• To achieve high-quality hydrogen production at high current densities using a low-cost, non-noble metal-based electrocatalyst.

Main Methods:

• Fabrication of a self-supporting electrode via electrodeposition and subsequent sulfurization.
• The electrode comprised oxygen-deficient molybdenum oxide (MoO3-) and cobalt phosphide (CoP) integrated onto nickel foam (NF).
• Characterization of the electrode's structure, composition, and electrochemical performance for HER.

Main Results:

• The MoO3-@CoP/NF electrode exhibited excellent pH-universal HER catalytic activity and high current density performance.
• Low overpotentials were recorded: 100 mV (alkaline), 135 mV (acid), and 400 mV (neutral) at 1 A cm-2.
• The performance surpassed that of many existing non-noble metal-based electrocatalysts.

Conclusions:

• The coupled MoO3-@CoP heterostructure demonstrates synergistic advantages, enhancing intrinsic catalytic performance.
• The developed electrode offers a promising pathway for designing advanced electrocatalysts for efficient hydrogen generation under diverse pH conditions.
• This work paves the way for practical, large-scale hydrogen production.