Incorporating Electron Acceptors into High-Entropy LDHs for Efficient and Stable Oxygen Evolution under Industrial Conditions

High-entropy 3d transition-metal layered double hydroxides (LDHs) with an entropy-stabilized effect exhibit excellent long-term durability during the OER, but their catalytic activity remains unsatisfactory. Here, we utilize high-entropy MnFeCoNiCu LDH as a model system and introduce an electron acceptor, Au nanoparticles, to elevate the valence state of metal sites and boost the catalytic activity, requiring only a low overpotential of 202 mV at 10 mA cm–2 in 1.0 M KOH electrolyte. Most importantly, under industrial conditions (30 wt % KOH, 60 °C), the Au@MnFeCoNiCu LDH||Pt/C pair requires only 1.76 V to deliver 200 mA cm–2 in an anion exchange membrane electrolyzer and sustains 700 h of long-term durability without any decay. X-ray absorption spectroscopy, in situ Raman spectroscopy, and density functional theory calculations reveal that the boosted catalytic activity and stability are attributed to the improved chemisorption of OER intermediates and the strengthened metal–oxygen bonding caused by the elevated valence state of metal sites, respectively.