Constructing a Hybrid Cu-ZIF/rGO Artificial Protective Layer toward Stable Dendrite-Free Zinc Anodes in Aqueous Zinc-Ion Batteries

Aqueous zinc-ion batteries (AZIBs) have attracted tremendous interest as emerging energy storage systems due to their high safety, low cost, and high theoretical specific capacity. The development of AZIBs is significantly impeded by parasitic reactions occurring at the electrode/electrolyte interface. It is now widely recognized that depositing a protective film on the zinc anode represents a reliable strategy for suppressing dendritic proliferation and mitigating water-induced parasitic reactions. This study reports the fabrication of a hybrid protective layer consisting of a reduced graphene oxide (rGO) aerogel and copper-doped ZIF (CZG). Benefiting from the synergistic effect between Cu-ZIF and rGO, the CZG coating facilitates smooth zinc electrodeposition and improves the cycle life of AZIBs. More than 800 h of uninterrupted operation was realized by the CZG@Zn symmetric cell at 5 mA cm–2 and 1 mA h cm–2. At a current density of 1 A g–1, the assembled CZG@Zn∥V2O3 full cell exhibits a specific capacity of 218.9 mA h g–1. Furthermore, it retained 83.2% of this value after 800 cycles at 3 A g–1. This work provides a dendrite-suppression strategy for achieving highly stable zinc anodes in AZIBs.