Wind-eroded landform-inspired organic salt protective coating for highly reversible zinc anodes

Uncontrolled side reactions and dendrite growth on zinc (Zn) anodes have significantly hindered the practical application of aqueous Zn-ion batteries (AZIBs). Herein, an organic salt coating composed of zinc citrate (ZC) with a wind-eroded landform morphology was in-situ fabricated on the Zn anode surface via a facile one-step citric acid etching process to mitigate these challenges. The ZC coating, characterized by its organic-inorganic hybrid composition, exhibits high ionic conductivity, elevated transference number, strong adsorption energy with Zn atoms, and robust corrosion resistance, effectively suppressing dendrite growth and side reactions. As a result, the Zn@ZC exhibits a superior cycling life of over 6000 h (>8 months) and a high average Coulombic efficiency of 99.9 % at 1 mA cm⁻². Moreover, the Zn@ZC||Zn₃V₃O₈ full cell delivers an initial capacity of 250.1 mAh g⁻¹ at 1 A g⁻¹ and retains 74.6 % of its capacity after 1000 cycles at 10 A g⁻¹. This high-performance organic salt coated Zn electrode presents a novel strategy for designing highly reversible Zn anodes, offering significant potential for advancing AZIB technology.