Quasi-Amorphous Metallic Nickel Nanopowder as an Efficient and Durable Electrocatalyst for Alkaline Hydrogen...

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Platinum is a benchmark electrocatalyst for hydrogen evolution reaction (HER).
• Developing cost-effective and efficient alternatives to platinum is crucial for HER.
• Nickel-based catalysts show promise but require further optimization for enhanced activity and durability.

Purpose of the Study:

• To synthesize a novel quasi-amorphous metallic nickel (QAMN) nanopowder catalyst.
• To evaluate the efficiency and durability of the QAMN catalyst for HER in alkaline media.
• To explore a new chemical synthesis route for amorphous metallic materials in catalysis.

Main Methods:

• A two-step chemical route was employed for the synthesis of QAMN nanopowder.
• Electrochemical performance was assessed using techniques like cyclic voltammetry and chronoamperometry.
• Catalyst stability was tested through accelerated and interrupted polarization experiments in alkaline solution.

Main Results:

• The QAMN electrocatalyst demonstrated near-zero overpotential at the cathodic onset for HER.
• It achieved a current density of 10 mA cm^-2 at an overpotential of only 240 mV.
• The catalyst exhibited excellent stability over tens of hours of operation in alkaline solution, outperforming previous nickel catalysts.

Conclusions:

• The QAMN catalyst offers significantly enhanced activity and durability for HER in alkaline media.
• The improved performance is attributed to both increased surface area and superior intrinsic activity.
• This study presents a viable chemical method for preparing amorphous metallic materials for advanced catalytic applications.