Bifunctional Organic Molecule Co‐Intercalated Aluminum Vanadate for Highly Reversible Aqueous Zinc‐Ion Batteries

Abstract Solvent engineering is a simple and efficient strategy for tuning layered cathodes in aqueous zinc‐ion batteries (AZIBs) that not only expands interlayer spacing and optimizes ion transport channels, but also reshapes the material's internal solvation environment and interfacial electrochemistry. However, single‐solvent intercalation suffers from limited regulation depth and poor structural stability, restricting its further application. In this study, layered aluminum vanadate (HAVO) is employed as the precursor to systematically investigate the differences between single‐solvent and mixed‐solvent intercalation in terms of structural evolution, redox potential, and cycling performance. The results demonstrate that mixed‐solvent intercalation offers synergistic enhancement and functional complementarity, enabling comprehensive improvements in structural stability, ion kinetics, and long‐term cycling stability, ultimately leading to the screening and identification of the high‐performing HAVO‐DA (HAVO‐DMF‐DMA) cathode. Furthermore, combined in situ and ex situ spectroscopic analyses reveal the HAVO‐DA cathode structural evolution during Zn 2+ insertion/extraction. This study provides new design principles for the multidimensional modulation of layered vanadium‐based cathode materials and demonstrates their potential for application in high‐performance AZIBs.