Hydrophilic‐Zincophobic Separator Enabling by Crystal Structure Regulation toward Stabilized Zn Metal Anode

Abstract Aqueous zinc‐ion batteries (ZIBs) hold significant promise for large‐scale energy storage. While considerable strides have been made in modifying separators, the challenge of developing dendrite‐free, corrosion‐resistant, and cost‐effective separators for achieving extended cycling performance of Zn anodes persists. In light of this, a TiO 2 coating separator to mitigate interfacial corrosion and passivation reactions, thereby facilitating high‐performance ZIBs is designed. This study delves into the influence of the loading amount and crystal phase of the TiO 2 coating layers on separator modification. Zn symmetric cells employing the anatase TiO 2 ‐modified glass fiber (A‐TiO 2 @GF) separator demonstrate superior Zn 2+ ion transport kinetics in a mild ZnSO 4 electrolyte, ensuring sustained long‐term stability and uniform Zn deposition. Furthermore, the reduced hydrogen evolution reaction (HER) activity of A‐TiO 2 coatings curbs H + ion migration, minimizing interfacial corrosion and HER. Consequently, the assembled Zn||CaV 8 O 20 zinc‐ion full cells demonstrate outstanding long‐term durability and impressive specific capacity, boasting a discharge capacity of 142 mAh g −1 after 1000 cycles. This work introduces a straightforward interface engineering strategy for creating efficient separators in zinc‐ion batteries, promoting uniform Zn deposition.