Palladium‐Induced Localized High‐Spin Environment Enhances Redox Kinetics for High‐Performance Aqueous Energy Storage

Abstract Regulating the surface electronic structure is crucial for the directional design of efficient energy storage materials. However, the mechanisms by which alterations in the spin microenvironment enhance intrinsic energy storage activity remain elusive. In this study, a localized high‐spin environment is successfully constructed by modifying the surface of NH 2 ‐UiO‐66 derivatives with high‐spin configuration palladium (Pd) nanoparticles. By integrating density functional theory calculations, in situ spectroscopy, and multiscale kinetic analysis, it is revealed that the introduction of high‐spin state Pd creates a Lewis acidic environment on the electrode surface, which significantly enhances the adsorption capacity and reactivity of electron‐rich intermediates. Moreover, the spin polarization effect increases the delocalization of d electrons and introduces new electronic states near the Fermi level, thereby markedly accelerating the kinetics of electrochemical reactions. Benefiting from this mechanism, electrodes with a localized high‐spin environment exhibit exceptional energy storage performance, with a high specific capacitance of 773.3 F g −1 at 1 A g −1 . This study offers novel theoretical insights and technical pathways for the design and fabrication of highly active energy storage electrodes.