Ultra-Low-Cost Hydrophobic Organic Coating for Highly Reversible Zinc Anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc-ion batteries (ZIBs) face challenges with dendrite formation and high additive costs.
• Current electrolyte additives often require high loading or have hydrophilic issues, limiting ZIB performance and scalability.

Purpose of the Study:

• To develop a cost-effective and scalable method for creating dendrite-free ZIBs.
• To engineer a hydrophobic electrolyte additive with ultra-low loading for enhanced ZIB performance and longevity.

Main Methods:

• Developed a facile immersion treatment to deposit a nanoscale hydrophobic 1,3-Di(o-tolyl)thiourea (DTH) layer on zinc anodes.
• Investigated the electrochemical performance of DTH-modified ZIBs using coin and pouch cell configurations.
• Evaluated additive cost efficiency and long-term cycling stability.

Main Results:

• Achieved nanoscale DTH layer deposition with ultra-low loading (5.37 × 10^-13 M) and exceptional cost efficiency (1.43 × 10^-7 USD Ah^-1).
• Demonstrated stable cycling over 2500 cycles at 2 A g^-1 in coin cells with minimal additive cost.
• Pouch cells exhibited 99.9% average coulombic efficiency and 72% capacity retention after 1200 cycles, with a high energy density of 143 Wh kg^-1.

Conclusions:

• The hydrophobic DTH layer effectively suppresses zinc dendrites and parasitic reactions, optimizing Zn electrochemistry.
• This low-cost, scalable strategy enables durable, high-performance aqueous ZIBs.
• The findings provide a foundation for developing cost-effective and scalable aqueous battery systems.