Boosting Zn2+ Intercalation in High‐Performance Aqueous Zinc‐Ion Batteries with Coupling‐Induced Biphase Interface

Abstract Effectively addressing the trade‐off between fast charging kinetics and long cycle life of aqueous zinc ion batteries (AZIBs) has proven challenging due to JahnTeller distortion and high lattice strain induced by inserted Zn 2+ ions in cathode structures. Herein, a hybrid cathode of NiCo 2 O 4 ‐MnO 2 with abundant electrochemical phase interfaces and interface coupling induced defects is developed via a simple electrochemical oxidation strategy to boost rich redox reactions. The formation of Ni─O─Mn and Co─O─Mn bonds promoted the electron transfer between the biphase interface, adjusted the electron density of the material body, effectively alleviated the electrostatic effect between Zn 2+ embedding and the main frame, and further maintained the stability of the structure and alleviated the dissolution of manganese. The resulting NiCo 2 O 4 ‐MnO 2 cathode exhibited a high reversible specific capacity of 343.5 mA h g −1 at a current density of 100 mA g −1 and retained 95.5 % of its initial capacity after 1000 cycles at a current density of 1 A g −1 . This discovery enriches insights into performance mechanisms at interfaces and paves the way for designing advanced energy storage materials.