An Artificial Interphase with Ion-Selective Pathways Enhancing Interfacial Kinetics for Highly Reversible Zinc Anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc metal batteries (AZMBs) are promising for next-generation energy storage but suffer from parasitic reactions and dendrite growth.
• Developing stable and efficient Zn anodes is critical for advancing AZMB technology.

Purpose of the Study:

• To engineer a novel artificial interphase for Zn anodes in AZMBs.
• To enhance Zn ion transport kinetics and suppress detrimental side reactions.
• To improve the overall cycling stability and lifespan of AZMBs.

Main Methods:

• Construction of a composite interphase (CCM) using carboxylated cellulose nanofiber (CNF) and β-cyclodextrin (β-CD) on a Zn anode.
• Characterization of the interphase structure and properties, including amorphous regions and hydroxyl group exposure.
• Electrochemical testing of the modified Zn anode in symmetric cells (Zn||Cu) and full cells (CCM@Zn||MnO2).

Main Results:

• The CCM interphase exhibits enhanced Zn2+ migration and ion-selective transport due to β-CD's steric hindrance and anion anchoring.
• The interphase effectively traps water, suppresses anode corrosion, and provides mechanical support against volume changes.
• CCM@Zn anodes demonstrated exceptional stability over 2200 h (1 mA cm-2/1 mAh cm-2) and 99.88% Coulombic efficiency over 1300 cycles (5 mA cm-2).
• CCM@Zn||MnO2 full cells retained 78.32% capacity after 2200 cycles.

Conclusions:

• The developed CCM interphase offers a viable strategy for interfacial engineering in AZMBs.
• This approach significantly improves the reversibility and cycle life of Zn anodes.
• The study provides a new pathway for developing high-performance and durable aqueous zinc metal batteries.