Solvent Exchange Induced Interfacial Ion‐Driving for Ag‐Gradient Membrane Enhancing Zn‐Ion Reaction Deposition in Dendrite‐Free Zinc Anodes

ABSTRACT Due to Zn 2+ uneven dispersion and aggregated deposition, zinc dendrite causes poor cycling stability in aqueous Zn‐ion batteries (AZIBs). Herein, we proposed constructing an Ag gradient hierarchical porous membrane to regulate reaction deposition and bottom‐up growth of Zn, by combining “electroless plating” with “phase inversion” not only utilizing polar functional groups (─COOH and ─C≡N) of membrane materials to adsorb Ag + , but regulating the solvent exchange rate to control the reduction rate of Ag + to induce gradient Ag distribution during membrane formation. The membrane is benefit to guide Zn 2+ dispersion and homogenization uniformly on the electrode surface via an interlaced porous structure. The Ag sites react with Zn 2+ to form Ag 5 Zn 8 during charging, which preferably induces Zn 2+ to deposit along the 002‐crystal plane on Zn surface. The synergistically promotional effect of porous membrane skeleton with Ag gradient and alloy phases as optimized deposition sites can enhance stable deposition on Zn anode. Zn//Cu and Zn symmetrical batteries with the interlayers exhibit high stability after 1100 cycles and 1200 h. The corresponding Zn//CVO coin cells and pouch cells are stable for 3000 and 1000 cycles. The work presents a new method to prepare a functional membrane interlayer to solve Zn dendrites in AZIBs.