Built‐In Electric Field Mediated High‐Entropy Transition Metal Heterojunction on Carbonized Wood Fiber for Industrial Oxygen Evolution Reaction with Enhanced Efficiency and Durability

Abstract Building efficient and durable electrodes for industrial‐scale hydrogen production is a major challenge. Here, a non‐precious‐metal high‐entropy Schottky heterostructure catalyst (FeCoNiMnCr HEA/HEO@NC/CWF) is prepared by simple carbonization using green and renewable wood fiber as the substrate and ZIF‐L as the template. The strong built‐in electric fieldsinduced by the heterojunction prompted the redistribution of electrons and the formation of electron‐rich HEO, which optimized the adsorption energy of intermediates such as ^* OOH. The HEA/HEO@NC/CWF achieves an ultra‐low overpotential of only 326 mV at 500 mA cm ^{− 2} in 1.0 m KOH and maintains operation for more than 1000 h at this current density (with a loss of activity of 3.2%). In addition, when applied as an anode catalyst in practical anion exchange membrane water electrolysis), it provided high activity of 0.5 A cm ⁻² at 1.57 V and shows good stability. This work provides a paradigm for designing durable high‐entropy electrocatalysts through Schottky interface engineering, offering significant potential for industrial water electrolysis applications.