Bioinspired Halloysite Nanotubes as a Triple-Synergistic Buffer Layer for Highly Stable Zinc Metal Anodes

Area of Science:

• Electrochemistry
• Materials Science
• Nanotechnology

Background:

• Aqueous zinc batteries face challenges with dendrite formation and side reactions due to slow ion kinetics.
• Existing protective coatings often compromise between stability and conductivity.

Purpose of the Study:

• To develop a bioinspired buffer layer using halloysite nanotubes (HNTs) for stable and fast ion transport in aqueous zinc batteries.
• To address the stability-conductivity trade-off in traditional battery interphases.

Main Methods:

• Design and implementation of a halloysite nanotube (HNT) buffer layer on zinc anodes.
• Experimental characterization and theoretical analysis of the HNT layer's interfacial regulation mechanism.
• Electrochemical testing of HNTs@Zn anodes and Zn||AC full cells under various conditions.

Main Results:

• The HNT layer regulates interfacial Zn2+ through a triple-synergistic mechanism: ion reservoir formation, water expulsion, and homogenized ion flux.
• HNTs@Zn anodes demonstrated exceptional stability over 2000 hours at 0.25 mA cm-2 and 800 hours at 10 mA cm-2.
• Zn||AC full cells achieved over 10,000 stable cycles with enhanced rate capability.

Conclusions:

• The bioinspired HNT buffer layer effectively suppresses dendrite formation and side reactions in aqueous zinc batteries.
• This mineral-based strategy offers a scalable and highly effective approach for developing long-lasting aqueous metal batteries.