Amphipathic Phenylalanine-Induced Nucleophilic-Hydrophobic Interface Toward Highly Reversible Zn Anode

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Aqueous Zn2+-ion batteries (AZIBs) offer safety and cost benefits but suffer from Zn anode dendrite growth and parasitic reactions.
• Developing stable Zn anodes is crucial for advancing AZIB technology.

Purpose of the Study:

• To enhance the reversibility and interfacial stability of the Zn anode in AZIBs.
• To investigate the use of phenylalanine (Phe) as a multifunctional electrolyte additive.

Main Methods:

• Introducing phenylalanine (Phe) as an additive into the electrolyte of AZIBs.
• Analyzing the coordination of Phe with Zn2+ ions and its adsorption onto the Zn anode.
• Characterizing the protective interphase formed by Phe using electrochemical methods.

Main Results:

• Phe optimizes the Zn2+ solvation environment and forms a protective interphase on the Zn anode.
• The interphase repels water and homogenizes Zn2+ flux, preventing dendrites.
• Zn||Zn cells achieved a cycle life of 5250 hours, and Zn||LMO full cells retained 77.3% capacity after 300 cycles.

Conclusions:

• Phenylalanine effectively improves the reversibility and interfacial stability of Zn anodes in AZIBs.
• The study demonstrates the potential of using biomolecules as additives for safer and more durable AZIBs.