Molecular Engineering of Functionalized Amino‐Acid Additives for Synergistic Stabilization of Zinc Metal Anode

Why It Matters

The additive directly addresses zinc anode degradation, a key barrier to commercial aqueous zinc batteries, enabling longer life and higher safety.

Key Takeaways

• GT additive combines glycine and tyrosine functional groups
• Carboxyl group coordinates Zn2+, improving desolvation
• Phenolic hydroxyl adsorbs on Zn crystal faces, directing growth
• Suppresses hydrogen evolution, reducing corrosion
• Enables dendrite‑free Zn deposition in symmetric and full cells

Pulse Analysis

Zinc‑based aqueous batteries promise low cost and intrinsic safety, yet their commercial rollout stalls because the Zn metal anode suffers from dendrite formation, hydrogen evolution, and uneven plating. Conventional electrolyte formulations lack the molecular precision to simultaneously manage ion solvation and surface chemistry, leading to rapid capacity fade. The new study leverages computational screening of functionalized amino acids, pinpointing N‑Glycyl‑L‑tyrosine (GT) as a dual‑action additive that reshapes the solvation sheath while anchoring to specific crystal facets, thereby harmonizing bulk ion transport with interfacial stability.

The GT molecule’s design is rooted in a clear division of labor: the glycine segment’s carboxyl group binds Zn2+ tightly, accelerating desolvation and smoothing ion flux toward the electrode. Meanwhile, tyrosine’s phenolic hydroxyl and carbonyl groups exhibit strong affinity for the (101) and (100) Zn planes, steering crystal growth toward the dense (002) orientation. This epitaxial guidance suppresses the formation of high‑energy protrusions that evolve into dendrites. By displacing water molecules at the interface, GT also curtails the parasitic hydrogen evolution reaction, mitigating corrosion and gas buildup—two major safety concerns in aqueous systems.

Experimental validation confirms that GT‑enhanced electrolytes deliver uniform Zn deposition, extending the lifespan of Zn||Zn symmetric cells and boosting the performance of Zn||NaV3O8 full cells. The broader implication is a scalable, molecule‑level design paradigm for electrolyte additives that can be adapted to other metal‑anion systems. As the industry seeks high‑energy, low‑cost storage solutions, such rational additive engineering could accelerate the transition of zinc batteries from laboratory prototypes to grid‑scale applications.