Improved Interface Stability and Zinc‐Ions Distribution Achieved by Functional Protective Layer Containing Abundant Oxygen Sites and Regular Channels for Long‐Life Zinc‐Metal Anodes

Abstract

Aqueous zinc (Zn)-ion batteries (AZIBs) have attracted much attention for the high safety, economy and nontoxic property, but further practical applications are still hindered due to the severe interfacial corrosion and annoying dendrite growth. Herein, a functional protective layer (FPL) containing abundant oxygen sites and regular channels is proposed as the surface coating to stabilize the Zn-metal anode. Specifically, transferred free water molecules and mitigated Zn-ions can be attracted by these polar oxygen sites, beneficially reliving corrosion behavior, reducing side reactions and inducing uniform Zn deposition. Furthermore, the cross-linked structure with opening channels of FPL benefits electrolyte to quickly arrive the electrode surface and maintain the superior movement of Znions. As a result, a superior cycling performance with high stability of 450 h at 5 mA cm À 2 and excellent rate behavior have been endowed by Zn electrode loading FPL. In the exploration of practical utilization, full battery consisting of Zn@FPL anode and cathode adopting commercial MnO 2 powder also exhibits an outstanding capacity retention of 98.9 % after 300 cycles at 0.5 A g À 1 . The proposed strategy of constructing a protective layer with functional sites and opening structure shows a good guiding significance for protecting Zn-metal anode.

Surface Engineering for Ultrathin Metal Anodes Enabling High-Performance Zn-Ion Batteries

“…On the other hand, the poor reversibility is usually associated with Zn dendrite growth during electrodeposition − as well as corrosion of the Zn metal in an acidic electrolyte that can result in H 2 gas generation, − electrochemical inactive byproducts, and irreversible Zn loss. − It is widely accepted that the surface orientation of a Zn metal anode is vital to the reversibility of a Zn-ion battery. , With a hexagonal symmetry, the most stable low index surfaces for Zn are the (002) and (101) surfaces under the Miller index convention. Zheng et al .…”