Robust Zinc Anode Enabled by Sulfonate-Rich MOF-Modified Separator

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc ion batteries (ZIBs) are promising for large-scale energy storage.
• Zinc dendritic growth and side reactions hinder ZIB commercialization.

Purpose of the Study:

• To develop a novel separator for ZIBs to stabilize the zinc anode.
• To inhibit zinc dendrite formation and improve battery performance.

Main Methods:

• Functionalizing glass fiber (GF) separators with a Zr-based MOF (UiO-66) rich in sulfonic acid groups.
• Creating a GF@UiO-S2 separator for enhanced zinc ion management.
• Testing Zn||Zn symmetric cells and Zn||MnO2 full cells with the modified separator.

Main Results:

• The GF@UiO-S2 separator ensured uniform ion flux and accelerated ion migration.
• It promoted uniform zinc plating/stripping and inhibited side reactions.
• Zn||Zn symmetric cells exceeded 3450 hours of cycling stability.
• Zn||MnO2 full cells retained 90% capacity after 1200 cycles.

Conclusions:

• The sulfonate-rich UiO-66 modified separator effectively stabilizes the zinc anode in ZIBs.
• This MOF-functionalized separator design offers a new strategy for robust ZIBs.
• The findings pave the way for safer and more durable large-scale energy storage solutions.