Micro‐Macro Regulation Through Co‐Intercalation of Inorganic–Organic for the V ₂ O ₅ · <i>n</i> H ₂ O Cathode Toward High‐Performance Aqueous Zinc‐Ion Batteries

ABSTRACT Vanadium oxides are deemed competitive cathode candidates for aqueous zinc‐ion batteries (AZIBs), benefited from their high theoretical capacity and multiple crystalline structures. However, the sluggish reaction kinetics, poor reversibility, and high solubility have hindered the practical application. In this study, through two‐step hydrothermal processes, K + ‐polyaniline (PANI) co‐intercalated hydrated vanadium oxide (K‐P‐VOH) with interlayer expansion (13.4 Å) and hierarchical structure is reported, realizing a structural regulation from micro to macro level. The K + and PANI intercalation can construct fast Zn 2+ transport channels, stabilize the layered structure, increase the electronic conductivity, and generate more lattice oxygen defects. Moreover, the interaction between Zn 2+ and VO layers is weakened, leading to accelerated Zn 2+ diffusion kinetics, lowered energy barriers, and enhanced cycling stability, based on the reaction kinetics analysis, theoretical density functional theory (DFT) calculations, and electrode process investigation. Consequently, the K‐P‐VOH cathode shows a discharge capacity of 305 mAh g −1 at 1.0 A g −1 , a superior rate capability of 185 mAh g −1 at 10.0 A g −1 , and an impressive capacity retention of 65.0% over 3000 cycles at 5.0 A g −1 . More importantly, in quasi‐solid‐state AZIBs, a high energy density (221.6 Wh kg −1 ) is achieved under a power density of 410.1 W kg −1 .