Abstract: Water electrolysis for hydrogen production has been recognized as an ideal pathway toward scalable green hydrogen manufacturing, owing to its renewable feedstock utilization, zero carbon emission byproducts, and high-purity hydrogen output. As the pivotal half-reaction in water splitting, the hydrogen evolution reaction (HER)suffers from sluggish kinetics that fundamentally limits energy conversion efficiency. Consequently, developing HER electrocatalysts with combined high activity and operational stability remains a critical challenge for practical implementation. In this work, we successfully synthesized nitrogen-doped molybdenum carbide nanorods with hierarchical porous structures by precisely regulating key synthesis parameters, including carbonization temperature and glucose content. Systematic characterizations via XRD, XPS, N2 physisorption-desorption analysis, Raman spectroscopy, SEM, and TEM were conducted to elucidate their phase composition, chemical state distribution, and morphological features. Electrochemical evaluations demonstrated that the optimized catalyst requires low overpotentials of merely 161 mV and 118 mV to achieve a current density of 10 mA/cm2 in 0.5 M H2SO4 and 1 M KOH, respectively. Remarkably, it exhibited exceptional operational stability, sustaining continuous HER operation for 200 hours at 10 mA/cm2 in acidic media and 120 hours under identical current density in alkaline condition.

Key words: Molybdenum carbide, Nanorods, Water splitting, Hydrogen evolution reaction