Enhanced Bifunctional Electrocatalysis for Zinc-Air Battery Using Porous Conductive Substrate with Abundant Anchoring...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• High-performance zinc-air batteries (ZABs) require efficient bifunctional electrocatalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR).
• Achieving balanced OER and ORR activity in a single catalyst is difficult due to differing reaction mechanisms during battery charging and discharging.

Purpose of the Study:

• To develop a scalable strategy for creating robust bifunctional electrocatalysts that enhance both OER and ORR activity.
• To improve the performance and cycling stability of zinc-air batteries through advanced catalyst design.

Main Methods:

• Integration of two-dimensional OER- and ORR-active materials onto a carbon-based conductive substrate using high-shear exfoliation.
• Characterization of the resulting heterostructure catalyst.
• First-principles calculations to assess chemical compatibility between catalyst components and the substrate.

Main Results:

• The heterostructure catalyst exhibited exceptional bifunctionality with a low overpotential difference of 0.63 V.
• The catalyst demonstrated excellent performance in scaled-up ZABs, achieving a peak power density of 1569 mW cm⁻².
• Outstanding cycling stability was observed, lasting over 300 hours (1800 cycles).

Conclusions:

• The study presents a versatile and scalable approach for designing multifunctional electrocatalysts.
• This method significantly advances the development of efficient energy conversion and storage technologies, particularly for ZAB applications.