Concentration-Driven Interfacial Amorphization toward Highly Stable and High-Rate Zn Metal Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Interfacial structure is crucial for suppressing dendrite growth and parasitic reactions in aqueous zinc metal batteries (AZMBs).
• Current research focuses on component fabrication, but local crystal structure's impact on interfacial properties requires further investigation.
• Scalable synthesis methods are essential for the commercialization of AZMBs.

Purpose of the Study:

• To develop a scalable method for transforming crystalline Zn metal interfaces to amorphous structures.
• To investigate the properties and benefits of amorphous zinc oxide (ZnO) at the Zn metal interface.
• To evaluate the performance enhancement of AZMBs using amorphous ZnO-coated zinc anodes.

Main Methods:

• A scalable concentration-controlled method was employed for crystalline to amorphous transformation of the Zn metal interface.
• Theoretical and experimental analyses were conducted to understand the properties of amorphous ZnO.
• Amorphous ZnO-coated zinc metal anodes (AZO-Zn) were fabricated and tested in AZMBs.

Main Results:

• The proposed method demonstrated exceptional scalability (>1 m²) and processing consistency (>30 trials).
• Amorphous ZnO exhibited advantageous properties including moderate adsorption energy, strong desolvation ability, and hydrophilicity.
• AZO-Zn anodes significantly improved cycling performance, achieving 1000 cycles at 100 mA cm⁻².
• A prototype AZO-Zn||MnO₂@CNT pouch cell maintained 91% of its capacity over 100 cycles.

Conclusions:

• Scalable synthesis of amorphous ZnO interfaces is achievable, offering a viable route for AZMB commercialization.
• The amorphous ZnO interface effectively suppresses detrimental interfacial reactions in AZMBs.
• This work presents a promising strategy for developing high-performance and durable aqueous zinc metal batteries.