Non-solvating additives regulate zinc deposition through anion-gated Stern-layer competition

Area of Science:

• Materials Science
• Electrochemistry
• Chemical Engineering

Background:

• Additive modulation of solvation structure enhances aqueous zinc-ion battery performance.
• Electrochemical mechanisms of non-solvation additives at the electric double layer and their impact on solid electrolyte interphase (SEI) evolution are poorly understood.

Purpose of the Study:

• To propose and investigate an anion-released interfacial engineering strategy for aqueous zinc-ion batteries.
• To elucidate the role of competitive spatial distribution of anions and cations in the Stern layer on interface formation.
• To decouple key kinetic processes in zinc deposition and understand their impact on battery cycling.

Main Methods:

• Anion-released interfacial engineering strategy.
• In situ spectra analysis.
• Theoretical simulations.
• Electrochemical performance evaluation.

Main Results:

• A robust, inorganic-organic hybrid interface was constructed through competitive spatial distribution of surface-affinitive anions and cationic regulators.
• Decoupled kinetic processes revealed fast Zn²⁺ transport within the SEI and moderated desolvation at the interface.
• Dendrite-free and highly reversible cycling of aqueous zinc-ion batteries was achieved.

Conclusions:

• The proposed strategy effectively engineers a stable interface for high-performance aqueous zinc-ion batteries.
• A mechanistic framework for the interfacial function of non-solvating additives was established.
• Refined insights into electrolyte design and interphase engineering for advanced aqueous metal batteries were provided.