Efficient Hydrogen Evolution Electrocatalysis at Alkaline pH by Interface Engineering of Ni₂P-CeO₂

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Effective non-noble-metal catalysts are essential for hydrogen evolution electrocatalysis in basic conditions.
• Developing efficient and durable electrocatalysts is a key challenge in renewable energy technologies.

Purpose of the Study:

• To demonstrate the facile construction of a Ni₂P-CeO₂ interface for alkaline hydrogen evolution reaction (HER).
• To investigate the catalytic performance and durability of the Ni₂P-CeO₂ nanosheet array.

Main Methods:

• Low-temperature phosphidation of a NiO-CeO₂ precursor to selectively form Ni₂P.
• Fabrication of a Ni₂P-CeO₂ nanosheet array on a Ti mesh.
• Electrocatalytic testing in 1.0 M KOH for HER.
• Density functional theory (DFT) calculations to understand the catalytic mechanism.

Main Results:

• The Ni₂P-CeO₂ nanosheet array exhibited excellent HER electrocatalytic activity, reaching 20 mA cm^-2 at an overpotential of 84 mV in 1.0 M KOH.
• The catalyst demonstrated superior durability compared to other reported Ni phosphide HER catalysts.
• DFT calculations indicated that the Ni₂P-CeO₂ interface promotes water dissociation and optimizes hydrogen adsorption.

Conclusions:

• The developed Ni₂P-CeO₂ interface serves as a highly effective non-noble-metal catalyst for alkaline HER.
• This work offers a promising strategy for designing advanced electrocatalysts for efficient hydrogen production.