Fluorine‐Mediated Electronic Modulation Optimizes Ru─H Bond Desorption Enabling Stable Hydrogen Evolution at Industrial‐Level Current Densities

Abstract Rapid performance degradation in alkaline hydrogen evolution catalysts, attributed to low intrinsic activity and bubble‐shielding effects under high current densities, poses a significant obstacle to achieving industrial hydrogen production. In response, a novel phosphorus‐doped activated carbon‐loaded ruthenium cobalt fluoride‐based heterostructured catalyst (Ru‐CoF 2 @PAC) is developed. Acting as an “electron trader”, this catalyst leverages the exceptional electron‐donating capability of fluoride anions bound to cobalt, effectively bringing the d‐band center of the Ru site close to the Fermi level. This optimizes the adsorption energy of the H intermediate (Ru‐H) in the Vomer step, subsequently facilitating rapid H conversion (H→H*). Moreover, the incorporated fluorine enhances catalyst hydrophilicity, significantly improving bubble diffusion kinetics at the catalyst surface and catalytic stability when operated under high current density. Remarkably, the Ru‐CoF 2 @PAC catalyst loaded with 1.1 wt.% Ru requires only 27 mV to achieve the 10 mA cm −2 current density needed to split water under alkaline conditions. Furthermore, the catalyst exhibits exceptional stability during at least 140 h of operation at 1200 mA cm −2 with negligible degradation. This study provides valuable insights for guiding the development of durable catalysts suitable for large‐scale industrial hydrogen production.