Recent Advances in Carbon-Based Bifunctional Oxygen Electrocatalysts for Zn-Air Batteries

Carbon-based composites have been known as the most promising bifunctional electrocatalysts for oxygen reduction/evolution reaction (ORR/OER) owing to their excellent electrocatalytic properties. In this Minireview, various types of carbon-based bifunctional oxygen electrocatalysts, including metal-free carbon and transition-metal-based carbon hybrids are reviewed to summarize progresses in rechargeable Zn-air batteries that are a promising technology to cope with the future energy demands. After a brief introduction to Zn-air batteries, some representative works are highlighted to understand the correlation between the electrocatalytic properties and the structure, the composition, and the synthesis method of carbon-based materials. Finally, the challenges and perspectives for future research of carbon-based bifunctional oxygen reduction/evolution catalysts are also outlined.