Dynamic Dissolution‐Deposition of Stainless Steel Boosts Industrial‐Grade Overall Water Splitting

ABSTRACT Developing highly efficient and durable bifunctional electrocatalysts for anion exchange membrane water electrolysis (AEMWE) is crucial for advancing green hydrogen production. Although Ru‐based catalysts are considered a potential alternative to Ir‐based ones, their practical application remains limited by sluggish kinetics, susceptibility to dissolution, and high cost. To address these challenges, this study proposes a dynamic potential activation strategy that enables stainless steel to form a self‐adaptive dissolution‐redeposition equilibrium under alkaline conditions. This process constructs a self‐supported S, Ru‐doped FeCr 2 O 4 structure (SSASR) on the stainless steel, significantly enhancing stability. The SSASR catalyst achieves low overpotentials of 182 mV for OER and 31 mV for HER at 10 mA cm −2 while maintaining exceptional stability for over 2000 h at 1 A cm −2 . In the AEMWE system, the electrode achieves a current density of 500 mA cm −2 at only 1.79 V, operates stably for 500 h, and exhibits a voltage decay rate (D v ) of 65 µV h −1 . Through experiments such as In situ differential electrochemical mass spectrometry (DEMS) and in situ Raman spectroscopy, combined with density functional theory (DFT) calculations, the presence of reactive oxygen species during the reaction was confirmed, and a lattice oxygen‐mediated mechanism (LOM) involving direct O─O coupling was revealed.