Utilizing Gradient Oxidized Alloys to Establish a Highly Stable Interfacial Chemical Environment for Aqueous Zinc‐ion Batteries

Abstract

AbstractThe research on rechargeable aqueous Zinc(Zn)‐ion batteries has expanded exponentially. However, the performance of Zn anodes during cycling and their commercial application is restricted by severe corrosion and dendritic formation. In this study, a facile approach is presented to address these challenges by introducing minute quantities of Zr(NO3)4 into the 3 m ZnSO4 electrolyte. The Zr(NO3)4 additive facilitates the creation of a protective layer comprising spatial gradient oxidation alloy (GOA) particles. The insulating zirconium‐based materials provide the necessary potential gradient to induce the Zn plate under the covering film. As a proof of concept, the in situ GOA coating anode exhibits exceptional cycling stability for 8000 cycles and an ultralow hysteresis voltage of 41 mV at current density of 5 mA cm−2. Furthermore, Density Functional Theory analyses reveal that the GOA coating anode homogenizes the electric field surrounding the Zn anode surface providing abundant zincophilic sites for Zn nucleation compared to bare Zn plates. This ensures uniform Zn deposition, preventing dendritic growth. In addition, the in situ characterization and computation of Gibbs free energy (ΔGH*) reveal that the GOA coating anode may effectively suppress the hydrogen evolution reaction.