Homogenizing Interfacial Electric Fields through a Nanoporous CaSO₄-Based Artificial SEI for Long-Lifespan Zinc Metal...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc-ion batteries offer high energy density, safety, and low cost.
• Practical application is hindered by capacity decay and short circuits due to uncontrolled zinc dendrite growth.

Purpose of the Study:

• To develop a cost-effective strategy for uniform zinc deposition.
• To suppress zinc dendrite formation and improve the cycling stability of zinc anodes.

Main Methods:

• Coating zinc anodes with nanoporous calcium sulfate (CaSO₄).
• In situ dendrite visualization, scanning electron microscopy (SEM), and laser confocal microscopy.
• Fabrication and testing of Zn@CaSO₄ symmetric cells and Zn@CaSO₄||MnO₂ full cells.

Main Results:

• The CaSO₄ coating effectively suppressed zinc dendrite growth.
• Zn@CaSO₄ symmetric cells demonstrated stable operation for over 1700 hours.
• The Zn@CaSO₄||MnO₂ configuration maintained 72.7% capacity retention after 1000 cycles at 1 A g^-1.

Conclusions:

• Nanoporous CaSO₄ serves as a low-cost, scalable protective layer for zinc anodes.
• The coating homogenizes the interfacial electric field, enhancing cycling stability and capacity retention.
• This strategy significantly improves the practical viability of aqueous zinc-ion batteries.