Industrial-compatible galvanostatic synthesis of oxygen-incorporated amorphous MoSx for dynamic alkaline water electrolysis

Developing robust, scalable, and cost-effective catalysts for alkaline water electrolysis (AWE) capable of withstanding intermittent renewable energy inputs is critical. Herein, we report a facile, industrially-compatible alkaline galvanostatic electrodeposition strategy to synthesize oxygen-incorporated amorphous molybdenum sulfide (MoS x ) catalysts on nickel foam, directly addressing the manufacturing gap between laboratory research and industrial fuel production. We elucidate that the alkaline environment (pH ≈ 10.16) serves a dual function: thermodynamically stabilizing the MoS 4 2− precursor against premature decomposition and facilitating the formation of a hierarchically porous, defect-rich amorphous network. This architecture synergistically integrates high-valence Mo 6+ species with abundant unsaturated S 2− active sites. Consequently, the optimized catalyst exhibits superior hydrogen evolution reaction (HER) performance, achieving a low overpotential of 59 mV at 10 mA cm −2 and a Tafel slope of 65.8 mV dec −1 , significantly outperforming potentiostatically prepared counterparts. Crucially, the electrode demonstrates exceptional resilience, maintaining >96% activity over 100 h at 200 mA cm −2 and stable voltage responses under drastic power fluctuations (0-1000 mA cm −2 ), simulating real-world renewable coupling. Post-catalytic analysis reveals a dynamic surface reconstruction mechanism driven by in-situ electron redistribution that sustains the active phase. This work provides a scalable blueprint for fabricating robust electrodes for dynamic, grid-scale hydrogen production.