Alkaline hydrogen evolution reaction (HER) is a cornerstone for efficient green hydrogen production via anion exchange membrane water electrolysis (AEMWE), yet suffering from sluggish water dissociation kinetics. Ruthenium (Ru)-based catalysts exhibit Pt-like activity at a fraction of the cost, but their performance is hampered by excessive hydroxide accumulation on Ru sites, a consequence of their overly strong oxygen affinity and suboptimal d-band center. Herein, we reported a class of Mo/V-dual-tailored Ru metallic glass nanosheets (Mo/V-Ru NSs) to enable spatial segregation of water dissociation sites (on Mo/V) from hydrogen evolution sites (on Ru), achieving the acceleration of alkaline HER electrocatalysis. The optimized Mo/V-Ru NSs deliver outstanding alkaline HER performance, with overpotentials of 36 and 86 mV at 10 and 100 mA·cm⁻², respectively, outperforming pure Ru counterparts and commercial Pt/C. Remarkably, the Mo/V-Ru NSs-based AEMWE can achieve a high current density of 100 mA·cm⁻² at a low cell voltage of 1.68 V and exhibit excellent durability for over 120 h. In-situ Fourier transform infrared (FT-IR) spectroscopy elucidates the role of Mo and V in water adsorption and O–H bond cleavage, synergistically lowering the water dissociation barrier. Density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations confirm enhanced water adsorption on Mo/V sites and preferential Ru-H coordination, supporting the site-segregation mechanism.

Proton exchange membrane water electrolysis (PEMWE) is a key technology for sustainable hydrogen production; however, its efficiency is limited by the sluggish kinetics and high overpotential of the anodic oxygen evolution reaction (OER). Although RuO₂ offers a cost-effective alternative to scarce IrO₂-based catalysts, its application is impeded by a fundamental trade-off between activity and stability under acidic conditions. Herein, we incorporate Hafnium (Hf) into the RuO₂ lattice to modulate the Ru oxidation state and oxygen vacancy concentration. The introduction of Hf suppresses Ru overoxidation, while controlled generation of oxygen vacancies minimizes lattice oxygen participation. The optimized Hf_0.1Ru_0.9O₂ catalyst exhibits a low overpotential of 187 mV at 10 mA·cm⁻² and outstanding durability, maintaining performance for 1500 h in 0.5 M H₂SO₄. Notably, a practical PEMWE device employing this catalyst achieves stable operation for over 600 h at 500 mA·cm⁻². A combination of in-situ differential electrochemical mass spectrometry (DEMS) and operando attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) reveal that Hf_0.1Ru_0.9O₂ facilitates oxygen evolution primarily through a multiple-pathway mechanism dominated by the adsorbate evolution mechanism (AEM) and the oxide pathway mechanism (OPM), with effectively suppressed lattice oxygen-mediated mechanism (LOM). These findings establish a new design principle for the development of durable acidic OER electrocatalysts.