Scalable progress for advanced bifunctional electrocatalysts for practical zinc-air batteries

Abstract

Zinc-air batteries (ZABs) deemed significant attention due to their high power/energy densities, sustainability, and environmental safety. The demand for ZABs has recently been amplified for harsh electrochemical operations (wide temperatures and high current densities). Bifunctional oxygen catalysts play a significant role in determining energy efficiency and cycle lifespan. Air cathodes damage their structural and dynamic performances due to the inevitable freezing of electrolytes for low temperatures and accelerate dehydration for high temperatures, restraining capacity and rate performances. Thus, understanding structural design strategies for bifunctional catalysts to promote ZABs performances is crucial. Herein, we illustrate the ZABs configurations and reaction kinetics over universal pH electrolytes and present challenges of bifunctional catalysts and ZABs. Further, the catalyst design concepts with defects and interface engineering have been discussed. Different types of metallic-, metal-free, MOFs/ZIFs- with 0D, 1D, 2D, 3D, and free-standing structures based ORR/OER catalysts are explored by describing insights for selectivity and design approaches of ZABs for wide temperature operations. Also, the challenges and outlooks for ZABs catalysts are systematically provided for feasible ZABs performances. © 2024 Elsevier Ltd