According to a research published in Advanced Energy Materials recently, a team led by Prof. HU Linhua. from Institute of Solid State Physics, Hefei Institutes of Physical Science (HFIPS), Chinese Academy of Science (CAS) found that the addition of serine cations (Ser⁺, C₃H₈NO₃) in the electrolyte of aqueous zinc-ion battery would lead to the preferred Zn (100) texture growth, which could effectively inhibit the Zn dendrite growth and ameliorate the reversibility and cyclability of batteries.

Aqueous zinc-ion batteries (AZIBs) have nowadays stimulated widespread attention for their safety, reliability, environmental friendliness, and cost-effectiveness. The severe Zn dendrite growth often induces poor reversibility and has become the major roadblock to the widespread commercialization of AZIBs. The (100) facet with high surface energy promotes the nucleation and deposition along the [100] direction into “tip-effect” active sites. Higher activity facet is often prone to induce side reactions, which would seriously deteriorate the Zn anode and the batteries’ stability. Thus, impeding the rampant [100]-direction growth is a simple and effective way to inhibit the dendrites and side reactions.

In this study, researchers conducted a (100) facet-termination engineering strategy employing serine (Ser, C₃H₇NO₃) as the interface structure conditioner into ZnSO₄ system. The adsorption of serine cations induces Zn (100) texture growth and inhibits harmful side reactions. The Zn//Cu batteries using the modified electrolyte achieved an average Coulomb efficiency of about 99.8% at the rate of 5 mA cm^-2 and 5 mAh cm^-2 for plating/stripping cycles, and the Zn//Zn symmetric batteries exhibited cycling performance of more than 800 hours.

In particular, Zn//V₂O₅ full battery delivers high specific capacity of 345.1 mAh g^-1 with a capacity retention of 74.1% over 2000 cycles at 5 A g^-1. At the meantime, the assembled pouch battery also has good stability, revealing the practical feasibility of Ser/ZnSO₄ electrolyte.

This research tailored the migration behavior of Zn²⁺ at (100)-facet by adsorbing ions, which provided a promising strategy for achieving the dominant texture of zinc anode at ion level, and was expected to be applied to other metal anodes with poor stability and reversibility.

The research has been supported by the HFIPS Director’s Fund.