Amphoteric Cellulose-Based Double-Network Hydrogel Electrolyte Toward Ultra-Stable Zn Anode.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous rechargeable zinc batteries (ARZBs) face challenges with zinc metal anodes, including dendrite formation and interfacial side reactions.
• These issues limit the practical application and long-term stability of ARZBs.

Purpose of the Study:

• To develop a novel hydrogel electrolyte for stabilizing zinc metal anodes in ARZBs.
• To address dendrite growth and parasitic reactions at the anode-electrolyte interface.

Main Methods:

• Introduction of an amphoteric cellulose-based double-network hydrogel electrolyte.
• Investigation of the hydrogel's ability to regulate zinc electro-deposition and ion flux.
• Analysis of the interaction between hydrogel functional groups and zinc ions to promote desolvation.

Main Results:

• The amphoteric hydrogel electrolyte effectively homogenized Zn2+ ion flux, promoting uniform zinc deposition on the Zn (002) crystal plane.
• Strong bonding between carboxyl groups and Zn2+ ions facilitated desolvation, suppressing side reactions.
• The Zn||Zn cell demonstrated ultra-stable cycling performance with a cumulative capacity of 7 Ah cm⁻² at 20 mA cm⁻² /20 mAh cm⁻².

Conclusions:

• The developed amphoteric hydrogel electrolyte significantly enhances the stability of zinc metal anodes in ARZBs.
• This approach provides a promising strategy for designing high-performance and stable aqueous rechargeable zinc batteries.