Hierarchical VOH@PANI Core–Shell Heterostructures With Expanded Interlayer Spacing and Conductive Polymer Interfacial Modification for High‐Performance Aqueous Zinc‐Ion Batteries

ABSTRACT A hierarchical VOH@PANI core–shell heterostructure is prepared by thermal annealing followed by polyaniline electrodeposition. The interlayer spacing of VOH is expanded from 1.08 to 1.32 nm, while the PANI outer shell simultaneously enhances electron transport and structural stability. As a result, the Zn//VOH@PANI full cell exhibits a high areal capacitance of 1.42 F cm − 2 at 1 mA cm − 2 , an exceptional energy density of 643.8 Wh kg − 1 , and superior cycling stability with 71% capacitance retention after 3000 cycles. Moreover, a flexible Zn–VOH@PANI battery is assembled, demonstrating stable electrochemical performance under various bending deformations. This work provides a viable strategy for designing high‐performance cathode materials toward practical aqueous zinc‐ion batteries.