Highly Reversible and Safe Zinc‐Metal Anodes Enabled by a Functional and Antibacterial Interfacial Layer

ABSTRACT Indisciplinable dendrite growth, harsh side reactions, and sluggish kinetics at the Zn electrode/electrolyte interface severely obstruct the commercialization of zinc‐metal batteries. Besides, the development of wearable devices has set a higher demand for the safety and biocompatibility of batteries. Herein, an in situ acid dipping approach is devised to spontaneously construct a functional and antibacterial interfacial layer containing carbonyl oxygen groups on the surface of zinc foils, using aqueous malic acid (denoted as MZ@Zn electrode) to tackle the above issues. The interfacial layer possesses satisfactory zincophilicity, promoting the ion kinetics and homogenizing the Zn deposition/dissolution. The MZ layer tightly adhered to the Zn electrode, and the deliberately exposed (0 0 2) Zn planes assure favorable anticorrosive quality. Moreover, the MZ layer possesses high antimicrobial activity, ensuring biological safety. Consequently, the MZ@Zn electrodes display ultralong cycle stability over 3500 h at 5 mA cm −2 . Furthermore, the full cells installed with LiFePO 4 /C (LFP/C) and NH 4 V 4 O 10 (NVO) cathodes exhibit superior electrochemical performances. Therefore, the stabilized zinc‐metal anode achieved by acid etching to spontaneously construct a functional interfacial layer provides a simple and effective strategy for aqueous zinc‐metal batteries.