Efficient Alkaline Hydrogen Evolution Reaction Using Superaerophobic Ni Nanoarrays with Accelerated H₂ Bubble...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Hydrogen bubbles adhering to catalysts impede water electrolysis performance.
• Understanding hydrogen bubble release mechanisms in the alkaline hydrogen evolution reaction (HER) is crucial.

Purpose of the Study:

• Investigate the impact of nanoscale surface morphologies on bubble release and HER performance.
• Utilize earth-abundant nickel (Ni) catalysts with controlled surface porosities.

Main Methods:

• Systematic investigation of Ni nanorods (NRs) with varying surface porosities.
• Analysis of surface aerophobicity, hydrophilicity, and HER performance.
• Evaluation of bubble release dynamics and catalytic activity.

Main Results:

• Ni catalyst with ≈52% porosity exhibited superaerophobic nature and superior HER performance.
• Superaerophobicity and open pore channels accelerated H2 bubble release.
• Significant improvements in geometric, specific, and mass activities were observed, especially at high current densities.

Conclusions:

• Highly porous Ni NRs with superaerophobic surfaces effectively release H2 bubbles, enhancing HER performance.
• Optimized surface morphology is key to improving catalyst efficiency.
• Combining superaerophobic Ni NRs with Pt and Cr can further enhance electrocatalytic performance.