Constructing a high-entropy nanoalloy by molten salt electroreduction for efficient bifunctional oxygen...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• High-entropy nanoalloys are crucial bifunctional oxygen catalysts for rechargeable zinc-air batteries.
• Phase separation is a significant challenge in synthesizing these nanoalloys, impacting their performance and stability.
• Developing stable and efficient catalysts is key to advancing sustainable energy storage solutions.

Purpose of the Study:

• To synthesize a phase-separated, high-entropy nanoalloy using a molten salt electroreduction method.
• To evaluate the catalytic performance of the synthesized nanoalloy for oxygen reduction and evolution reactions.
• To assess the long-term stability and efficiency of the nanoalloy in rechargeable zinc-air batteries.

Main Methods:

• Molten salt electroreduction was employed to synthesize the high-entropy nanoalloy, preventing phase separation.
• The catalyst's bifunctional oxygen catalytic activity was measured by its overpotential (ΔE).
• Rechargeable zinc-air batteries were assembled using the catalyst to evaluate power density, specific capacity, and cycling stability.

Main Results:

• The synthesized high-entropy nanoalloy demonstrated a low bifunctional oxygen overpotential of 0.72 V.
• Zinc-air batteries utilizing this catalyst achieved a peak power density of 216.7 mW cm⁻² and a specific capacity of 784.4 mAh g⁻¹.
• Exceptional cycling stability exceeding 1200 hours was observed, positioning it among the best reported catalysts.

Conclusions:

• The molten salt electroreduction method effectively prevents phase separation in high-entropy nanoalloys.
• The developed nanoalloy exhibits superior bifunctional oxygen catalytic activity and stability for rechargeable zinc-air batteries.
• This work presents a promising pathway for developing advanced catalysts for sustainable energy storage applications.