Heterostructured Interface Enables Uniform Zinc Deposition for High-Performance Zinc-Ion Batteries

Zinc metal has considerable potential as a high-energy anode material for aqueous batteries due to its high theoretical capacity and environmental friendliness. However, dendrite growth and parasitic reactions at the electrode/electrolyte interface remain two serious problems for the Zn metal anode. Here, the heterostructured interface of ZnO rod array and CuZn layer is fabricated on the Zn substrate (ZnCu@Zn) to address these two issues. The zincophilic CuZn layer with abundant nucleation sites ensures the initial uniform Zn nucleation process during cycling. Meanwhile, the ZnO rod array grown on the surface of the CuZn layer can guide the subsequent homogeneous Zn deposition via spatial confinement and electrostatic attraction effects, leading to the dendrite-free Zn electrodeposition process. Consequently, the derived ZnCu@Zn anode exhibits an ultra-long lifespan of up to 2500 h with symmetric cells at the current density and capacity of 0.5 mA cm /0.5 mA h cm . Besides, a remarkable cyclability (75% retention for 2500 cycles at 2 A g ) is achieved in the ZnCu@Zn||MnO full cell with a capacity of 139.7 mA h g . This heterostructured interface with specific functional layers provides a feasible strategy for the design of high-performance metal anodes.