Electrofabricated Oxygen-Terminated Zincophilic ZnCoAl-LDH Functional Layers for Reversible Zinc Metal Anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Rechargeable aqueous zinc-based batteries offer a safe and cost-effective solution for grid-scale energy storage.
• Dendritic growth and parasitic reactions are significant challenges hindering their practical application.
• Existing artificial interface layer (AIL) fabrication methods often introduce impedance due to binders.

Purpose of the Study:

• To develop a novel, binder-free artificial interface layer (AIL) for zinc anodes in aqueous batteries.
• To address dendritic growth and improve the cycling stability and Coulombic efficiency of zinc anodes.
• To investigate the role of interfacial chemistry in guiding uniform zinc deposition.

Main Methods:

• An integrated electrosynthesis approach was used to construct a ZnCoAl-layered double hydroxide interlayer enriched with zincophilic oxygen groups (LDH-O@Zn) on Zn anodes.
• The LDH-O@Zn modified anodes were tested in symmetric cells and full cells with a NaV3O8·nH2O cathode.
• Electrochemical performance, including cycling stability, Coulombic efficiency, and capacity retention, was evaluated.

Main Results:

• The binder-free LDH-O@Zn layer effectively suppressed dendritic growth and corrosion.
• Symmetric cells demonstrated stable cycling over 2500 hours at 10 mA cm⁻² with an average Coulombic efficiency of 99.73% over 9000 cycles.
• Full cells maintained 86.83% capacity retention after 2800 cycles at 1 A g⁻¹ with a high-mass-loading cathode.

Conclusions:

• The developed LDH-O@Zn interlayer, inspired by biomedical targeting, provides a physical barrier and dynamically regulates Zn nucleation and desolvation.
• Terminal polar groups and unimpeded Zn²⁺ channels in the interlayer guide homogeneous Zn(002) deposition.
• This work highlights the importance of interfacial terminal group chemistry for creating scalable and durable zinc anodes for practical aqueous batteries.