A Bifunctional Organosilane Additive for Dynamic pH Regulation and Interfacial Protection in Aqueous Zinc-Ion...

Area of Science:

• Electrochemistry
• Materials Science

Background:

• Aqueous zinc-ion batteries are promising for grid-scale energy storage.
• Zinc dendrite growth and hydrogen evolution reaction hinder battery performance.

Purpose of the Study:

• To develop a novel additive, Ormosil, to address challenges in aqueous zinc-ion batteries.
• To improve electrode protection and electrolyte stability.

Main Methods:

• Ormosil, a water-soluble organosilane, was synthesized and added to the electrolyte.
• Electrochemical performance was evaluated using zinc foil electrodes and NVO cathodes.
• The interaction of Ormosil with the zinc electrode and zinc ions was investigated.

Main Results:

• Ormosil formed protective Si─O─Zn bonds on the zinc foil, preventing corrosion.
• It facilitated the formation of a stable solid-electrolyte-interphase (SEI) layer for efficient zinc-ion transport.
• The additive suppressed hydrogen evolution and improved cycling stability to 1000 hours at 10 mA cm⁻².
• A full cell with an NVO cathode achieved 76.60% capacity retention, outperforming the control.

Conclusions:

• Ormosil effectively protects zinc electrodes and restructures the electrolyte.
• The additive enhances the stability and performance of aqueous zinc-ion batteries.
• Ormosil presents a viable solution for developing high-performance grid-scale energy storage systems.