A Theory-Driven Moderation Strategy for Electrolyte Design Unlocks Stable Aqueous Zinc Deposition

Area of Science:

• Electrochemistry
• Materials Science
• Computational Chemistry

Background:

• Understanding additive effects on zinc deposition is crucial for aqueous zinc-ion batteries.
• Theoretical screening of additives is needed to optimize electrolyte performance and stability.

Purpose of the Study:

• Establish a non-extremum empirical model for screening electrolyte additives.
• Balance additive properties with solvation and interface stability in zinc-ion battery electrolytes.

Main Methods:

• Theoretical calculations of solvation capability, adsorption strength, and interfacial electrostatic properties.
• Utilized a model system of structurally analogous alcohol-based molecules.
• Applied the Sabatier principle for performance evaluation.

Main Results:

• Identified 1,6-hexanediol as an additive with balanced molecular parameters.
• Demonstrated significantly enhanced reversibility of zinc deposition/stripping.
• Achieved extended cycling lifespan of up to 2,600 hours with optimal electrochemical performance.

Conclusions:

• A balanced set of molecular parameters is critical for modulating Zn2+ coordination and interface stability.
• The proposed theoretical screening model provides a new perspective for rational additive selection.
• Expanding selection criteria is vital for optimizing interfacial stability in zinc-ion batteries.