Interfacial engineering of CoP/CoS₂ heterostructure for efficiently electrocatalytic pH-universal hydrogen production

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient, durable, and cost-effective catalysts is vital for hydrogen generation through water electrolysis.
• Interfacial engineering offers a promising approach to enhance the catalytic activity of electrode materials for the hydrogen evolution reaction (HER).

Purpose of the Study:

• To design and synthesize a novel heterogeneous catalyst for efficient hydrogen evolution reaction (HER).
• To investigate the catalytic performance and durability of the new material across a range of pH conditions.

Main Methods:

• Fabrication of cobalt phosphide-cobalt sulfide (CoP/CoS2) nanowire arrays on carbon cloth (CC) using a phosphidation and sulfidation treatment.
• Electrochemical evaluation of the CoP/CoS2/CC catalyst for HER in alkaline, acidic, and neutral media.
• Testing of a CoP/CoS2||NiFe layered double hydroxide electrolyzer for hydrogen production.

Main Results:

• The CoP/CoS2/CC catalyst exhibited excellent pH-universal HER activity, requiring low overpotentials (e.g., 58.1 mV in acidic conditions) to achieve a current density of 10 mA cm-2.
• The catalyst demonstrated superior electroactivity in 1.0 M KOH, outperforming commercial Pt-C/CC at current densities above 50 mA cm-2.
• The integrated electrolyzer showed high catalytic performance and stability, surpassing the benchmark Pt-C||IrO2 system.

Conclusions:

• The developed CoP/CoS2/CC catalyst offers an effective pathway for high-performance, low-cost hydrogen production.
• Interfacial engineering and synergistic effects in heterostructures are key to enhancing HER electrocatalysis.
• This work provides a promising strategy for fabricating advanced electrocatalysts for future hydrogen energy applications.