Enhancing Secondary Alkaline Battery Performance: Synthesis and Electrochemical Characterization of Zn Anodes, Based on ZnO@C Core‐Shell Nanoparticles

Abstract

While alkaline Zn batteries, like traditional rechargeable aqueous batteries, boast an advantage in terms of energy density, their progress has been hampered by concerns related to the anode. These concerns include issues like Zn dendrites, self‐corrosion, passivation, shape change, and the hydrogen evolution reaction (HER). To tackle these challenges, we have introduced a nanostructuring approach for the anode, employing carbon‐coated ZnO nanoparticles (ZnO@C) as the active material. In this study, we synthesized ZnO@C nanoparticles in an environmentally sustainable and scalable manner to address passivation and dissolution issues jointly. Nanoscale ZnO particles effectively prevent passivation, while carbon shell slows down the dissolution of zincate. The Zn anode exhibits a significant performance boost when compared to Zn foil and bare ZnO nanoparticles, even when subjected to demanding conditions (without the use of ZnO‐saturated electrolyte). This rechargeable Zn anode marks a significant step toward the realization of practical, high‐energy rechargeable aqueous batteries, such as Zn‐air batteries.