Critical Solvation Structures Arrested Active Molecules for Reversible Zn Electrochemistry

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Aqueous zinc-ion batteries (AZIBs) offer safe and economical energy storage.
• Zinc anode instability, including side reactions and dendrites, limits AZIB performance.

Purpose of the Study:

• To develop a critical solvation strategy for reversible zinc electrochemistry in AZIBs.
• To enhance the stability and cycle life of zinc anodes in aqueous electrolytes.

Main Methods:

• Introducing acetonitrile as a polar molecule to form a "catcher" for active molecules.
• Stabilizing the [Zn(H2O)6]2+ solvation structure to inhibit free water molecules.
• Investigating the desolvation process at the zinc anode interface.

Main Results:

• Achieved stable cycling for 2250 hours in Zn||Zn symmetric batteries at 1 mAh cm-2.
• Demonstrated 99.2% capacity retention over 10,000 cycles in Zn||V6O13 full batteries at 10 A g-1.
• Successfully inhibited dendrite formation and side reactions at the zinc anode.

Conclusions:

• The critical solvation strategy effectively stabilizes zinc electrochemistry in AZIBs.
• Acetonitrile acts as a "catcher" to ensure stable Zn2+ desolvation and prevent detrimental side reactions.
• This approach provides a pathway for developing high-performance and durable AZIBs.