Highly\nReversible Dendrite-Free Zinc Anode Enabled\nby a Bilayered Inorganic-Metal Interface Layer

The\nunavoidable dendrite growth and side reactions are two major\nissues that lead to unsatisfactory cycling stability of the Zn metal\nanode and premature battery failure, which constrains the wide practical\napplication of aqueous Zn-ion batteries. Herein, a bilayered zinc\nfluoride–indium interface-modified zinc anode (ZnF<sub>2</sub>–In@Zn) is in situ-constructed to solve these two issues through\na simple solution-dipping strategy. The outer ZnF<sub>2</sub> layer\nassures sufficient desolvation of hydrated Zn<sup>2+</sup> and even\nZn<sup>2+</sup> flux; meanwhile, the interior In layer further contributes\nto the uniform distribution of the electric field and lower energy\nbarrier of Zn<sup>2+</sup> nucleation, achieving dendrite-free and\nside reaction-free Zn deposition. With synergistic regulation from\nthe bilayered composite interface, the ZnF<sub>2</sub>–In@Zn\nanode exhibits outstanding cycling stability (over 4200 h at 1 mA\ncm<sup>–2</sup>), achieving a cumulative capacity of over 5250\nmAh cm<sup>–2</sup> even under a high current density of 5\nmA cm<sup>–2</sup>. This work proposes an advanced understanding\nof reasonable interface engineering for tackling multiple challenges\nfaced by metal anodes.