Constructing 3D Crosslinked Macromolecular Networks as a Highly Efficient Interface Layer for Ultra-Stable Zn Metal...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc ion batteries (AZIBs) offer high capacity and safety but suffer from dendrite growth and parasitic reactions at the zinc anode.
• These issues limit the durability and practical application of AZIBs.

Purpose of the Study:

• To develop an interface layer for zinc metal anodes in AZIBs to suppress dendrite formation and parasitic reactions.
• To improve the cycling stability and performance of AZIBs.

Main Methods:

• Fabrication of a 3D crosslinked macromolecular network using zinc ion-bonded potato starch (StZ) as an interface layer on Zn foil (StZ-Zn).
• Utilized density functional theory (DFT), molecular dynamics (MD), COMSOL simulations, and in situ Raman spectroscopy to investigate the interface properties.
• Tested StZ-Zn||StZ-Zn symmetric cells and StZ-Zn||NaV3O8·1.5H2O full cells.

Main Results:

• The StZ interface layer effectively inhibited hydrogen evolution and regulated Zn2+ flux by facilitating desolvation and reducing water concentration.
• Demonstrated dendrite-free zinc deposition and uniform Zn2+ transport.
• StZ-Zn||StZ-Zn symmetric cells achieved a lifespan of 4800 h at 5 mA cm-2 with 12000 mAh cm-2 cumulative capacity.
• Full cells exhibited stable operation for 2500 cycles at 5 A g-1 with 92% capacity retention.

Conclusions:

• The developed StZ interface layer is a promising strategy for enhancing the performance and durability of zinc metal anodes in AZIBs.
• This approach addresses key challenges in AZIB technology, paving the way for safer and more efficient energy storage solutions.