Aluminum‐Directed Amphoteric Self‐Reconstruction in High‐Entropy AlFeCoNiCuCr‐LDH for Efficient Overall Water Splitting

ABSTRACT Electrochemical self‐reconstruction in high‐entropy catalysts governs their catalytic activity and stability. However, uncontrolled structural evolution often led to performance degradation, rendering the precise modulation of these interfacial pathways a major bottleneck. Herein, we report an aluminum‐containing high‐entropy layered double hydroxide (Al‐HELDH) and elucidate its amphoteric self‐reconstruction mechanism. During electrochemical activation, selective leaching of amphoteric aluminum species significantly enhances access to metal active sites while inducing formation of surface‐enriched Al(OH) x hydroxyl layers. This hydroxylated interface effectively regulates adsorption and dissociation processes, stabilizing the reconfigured catalytic surface and simultaneously boosting catalytic activity and durability. In situ spectroscopy and density functional theory calculations confirm Ni as the primary catalytic center, with other metal species cooperatively modulating the local electronic environment. Benefiting from synergistic high‐entropy effects and a functional Al(OH) x interface layer, reconstructed Al‐HELDH significantly reduces interfacial energy barriers for key reaction steps and accelerates reaction kinetics. The catalyst exhibits overpotentials of 64 and 226 mV for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at a current density of 10 mA cm −2 , respectively, while maintaining stable operation for over 1000 h. This work establishes a reconstruction‐based design strategy, providing a robust pathway for developing non‐precious metal bifunctional catalysts for sustainable hydrogen production.