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

Abstract

Efficient and robust bifunctional electrocatalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are critical for high-performance zinc-air batteries (ZABs). However, balancing OER and ORR activity in a single catalyst remains challenging due to the different mechanisms during charging and discharging. Here, a scalable strategy is presented for enhancing both reactions by integrating two-dimensional OER- and ORR-active components onto a carbon-based conductive substrate with abundant anchoring sites, via high-shear exfoliation. The heterostructure catalyst demonstrates exceptional bifunctionality, achieving an extremely low overpotential difference of 0.63 V. First-principles calculations confirm a strong chemical compatibility between the active components and substrate. In scaled-up ZAB applications, the catalyst delivers a high peak power density of 1569 mW cm-2, and an outstanding cycling stability over 300 h (1800 cycles). This work highlights a versatile approach for designing multifunctional electrocatalysts, advancing scalable energy conversion and storage technologies.