Quasi-Solid Electrolyte Interphase Boosting Charge and Mass Transfer for Dendrite-Free Zinc Battery

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Zinc metal batteries face challenges in practical application due to dendritic growth of metal anodes.
• Limited charge and mass transfer at the electrode/electrolyte interface hinders zinc metal reversibility.

Purpose of the Study:

• To enhance zinc metal reversibility and mitigate dendrite formation.
• To develop a quasi-solid interphase for improved zinc ion transport.

Main Methods:

• Fabrication of a quasi-solid interphase using defective metal-organic framework (MOF) nanoparticles (D-UiO-66) on a zinc surface.
• Utilizing two types of zinc salt electrolytes and anchoring anions onto Lewis acidic sites within the MOF.
• Investigating the synergistic effects of MOF channels and anchored anions on zinc ion transport.

Main Results:

• The quasi-solid interphase significantly boosts charge and mass transfer of Zn²⁺.
• Achieved high zinc transference number, good ionic conductivity, and high Zn²⁺ concentration near the anode.
• Demonstrated an unprecedented average coulombic efficiency of 99.8% in a Zn||Cu cell and excellent cycling stability in Zn||MnO₂ and Zn||NH₄V₄O₁₀ cells.

Conclusions:

• The developed D-UiO-66 based quasi-solid interphase effectively suppresses zinc dendrite growth.
• This approach enhances the reversibility and electrochemical performance of zinc metal anodes.
• The study proves the feasibility of this interphase for practical zinc metal battery applications.