Phase‐Regulated Interfacial Polarization in High‐Entropy Materials Enhances Fenton‐Like Oxidation and Self‐Induced Coagulation for Environmental Remediation

Abstract High‐entropy materials (HEMs) have garnered significant interest in Fenton‐like catalysis for water treatment due to their tailorable structures and unique high‐entropy effects. However, conventional single‐phase solid‐solution HEMs often suffer from rigid active sites, untunable electronic structures, and non‐equilibrium phase transitions induced by lattice stress, limiting their application in multi‐step Fenton‐like reactions. To overcome this, a Rhombohedral (R‐3c) phase is successfully derived within a Face‐Centered Cubic (FCC)‐based HEM by employing amorphous carbon to disrupt the crystal structure and optimizing calcination conditions. Facilitated by citric acid decomposition promoting oxygen penetration into the metal lattice, this optimization yielded polycrystalline CoCuMnAlLaCr composites with abundant structural defects and phase interfaces. The intense polarization from built‐in electric field at FCC/R‐3c interfaces enabled ultrafast peroxymonosulfate activation, achieving over 93.6% pollutant removal within 2 min across pH 3–10, with robust resistance to real water matrix interferences. Crucially, phase reconstruction combined with manganese incorporation enabled multi‐step pathways: a self‐initiated MnO 2 ‐based coagulation process followed initial oxidation step, efficiently recycling leached trace metal ions and removing intermediates. This work breaks the limitations of single‐phase HEMs by synergistically combining multiple phase interfaces with distinct work functions and creating a dual oxidation‐coagulation system, providing a novel framework for designing advanced environmental catalysts.