Recent advances and challenges of cobalt-based materials as air cathodes in rechargeable Zn-air batteries

To mitigate decades of extreme reliance on fossil fuels that have resulted in an increasingly serious energy shortage and environmental problems, extensive research on new clean renewable energy and energy storage technologies with high effectiveness, low cost, and environmental friendliness is required. Zinc-air batteries (ZABs) are effective tools for converting and storing renewable energy. Unfortunately, the low kinetics of the air cathode, as well as the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are the principal drawbacks of ZABs. This necessitates the development of high-performance catalysts to accelerate the reaction rates and improve their efficiency. Cobalt-based carbon is an excellent choice for oxygen electrocatalysts due to its low cost, high activity, and stability. Recent advancements in cobalt-based carbon materials used as elec-trocatalysts in ZABs, as well as the characterization techniques and synthesis procedures, are covered in this paper. It also introduces and analyzes the fundamental mechanisms of ORR and OER electrocatalysis. Finally, we give a description of the present difficulties and potential future developments in the creation of novel high efficiency and bifunctional electrocatalysts.