Progress of Aqueous Rechargeable Zn–CO2 Batteries with a Focus on Cathode Bifunctional Catalysts

Abstract

Aqueous rechargeable Zn–CO<inf>2</inf> batteries are emerging as a promising technology for sustainable energy storage and carbon dioxide (CO<inf>2</inf>) utilization, owing to their high safety, theoretical capacity, and product diversity. Despite their significant theoretical potential, the application of Zn–CO<inf>2</inf> batteries is hindered due to several challenges, including low product-added value, low current density, poor cycle stability, and excessively high overpotential. These issues hinder the widespread use of Zn–CO<inf>2</inf> batteries. Cathode bifunctional catalysts, which can promote the CO<inf>2</inf> reduction reaction while lowering the reaction energy barrier for the oxygen evolution reaction, have garnered research interest in recent years. However, a systematic summary is rarely reported. This review mainly focuses on the cathode catalysts of aqueous rechargeable Zn–CO<inf>2</inf> batteries, summarizing current research progress in terms of devices, reaction mechanisms, and bifunctional catalysts. This review also discusses existing challenges and prospects, offering enlightenment for the future research of Zn–CO<inf>2</inf> batteries.