Atomic‐level Geometric Engineering Modulating d ‐ s Hybridization of Ordered RuGa Intermetallic for Efficient Hydrogen Electrocatalysis

ABSTRACT Ruthenium (Ru) is a promising alternative to platinum for hydrogen oxidation (HOR) and evolution (HER), yet its intrinsically strong hydrogen binding, governed by its atomic geometry, limits activity. Herein, we report a highly efficient and durable RuGa intermetallic catalyst with an atomically ordered structure that disrupts the geometric symmetry of Ru, thereby optimizing hydrogen adsorption. The catalyst achieves a specific exchange current density of 1.02 mA cm ^{− 2} and a mass activity of 1850 mA mg _Ru ^{− 1} for HOR, 5.5‐ and 3‐fold higher than Ru/C, respectively. For HER, it requires only 11 mV to reach 10 mA cm ^{− 2} and shows a 7.4‐fold higher mass activity than Ru/C. Remarkably, it exhibits negligible degradation after 1000 HOR and 10 000 HER cycles. Density functional theory calculations and in situ Raman analyses reveal that geometric engineering enhances Ru 4d ‐H 1s hybridization, weakens Ru–H bonding, and lowers hydrogen adsorption energy, thus accelerating HER/HOR kinetics and preventing active‐site poisoning. This work establishes a paradigm for designing high‐performance Ru‐based electrocatalysts through atomic‐level geometric modulation.