An Atomic-to-Macroscale Assembled Ni/MoO₂ Electrode for High-Efficiency and Long-Life Hydrogen Production

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Cost-effective green hydrogen production relies on efficient alkaline water electrolysis.
• Developing active and durable electrodes for high-current-density operation is critical.

Purpose of the Study:

• To create an integrated Ni/MoO2 electrode with atomic heterointerfaces and triscale porosity.
• To enhance hydrogen evolution reaction (HER) performance in alkaline water electrolysis.

Main Methods:

• Atomic-to-macroscale assembly of Ni/MoO2 electrodes.
• Characterization of electrode structure and properties.
• Electrochemical testing at high current densities.
• Theoretical analysis of catalytic mechanisms.

Main Results:

• The Ni/MoO2 electrode achieved an overpotential of 145 mV at 1 A cm⁻² in 1 M KOH, outperforming commercial Pt/C.
• Demonstrated stable operation for over 3500 hours.
• Achieved a cell voltage of 1.80 V with 4.3 kWh Nm⁻³ H₂ energy consumption under industrial conditions, with >1000 h durability.

Conclusions:

• The integrated Ni/MoO2 electrode exhibits superior activity and durability for alkaline water electrolysis.
• Triple-enhancement effects include boosted intrinsic activity, enhanced mass transfer, and improved structural stability.
• This electrode offers a promising pathway for cost-effective green hydrogen production.