Silver Nanowire Aerogel Support Promotes Stable Hydrogen Evolution Reaction at High Current Density

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Electrocatalyst stability is crucial for efficient hydrogen evolution reaction (HER) and hydrogen energy production.
• Developing robust electrocatalysts is essential for practical applications in renewable energy.

Purpose of the Study:

• To investigate the use of silver nanowire aerogel-based support (AABS) for enhancing the long-term stability of HER catalysts.
• To prepare and characterize a nickel phosphide catalyst supported on AABS (Ni2P-Ni5P4@AABS) for HER.

Main Methods:

• Fabrication of nickel phosphide nanoparticles on a silver nanowire aerogel-based support.
• Electrochemical characterization of the catalyst's performance in the hydrogen evolution reaction using techniques like i-t stability tests.
• Analysis of catalyst structure and properties to understand the source of enhanced stability.

Main Results:

• The Ni2P-Ni5P4@AABS catalyst demonstrated an overpotential of 687 mV at 1 A cm-2 for HER in 0.5 M H2SO4.
• Exceptional long-term stability was observed, with performance maintained for 42 days at high current densities (0.5-1 A cm-2).
• The enhanced performance is attributed to rapid electron transport, increased accessible active sites, and support-induced catalytic activity.

Conclusions:

• Silver nanowire aerogel-based supports can significantly improve the stability of electrocatalysts for the hydrogen evolution reaction.
• The Ni2P-Ni5P4@AABS catalyst represents a promising material for efficient and durable hydrogen production.
• A phenomenological two-channel electron transport model provides insights into catalyst design for energy applications.