Abstract

In this work, we report a rapid, one-step continuous-wave CO₂ laser–induced thermal shock process for synthesizing Ru/RuO₂ with coherent metallic–oxide interfaces. The ultrafast laser process enables the precise creation of an electronically coupled Ru/RuO₂ interface with superior bifunctional activity toward both the hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR). Notably, the optimized Ru/RuO₂-1 catalyst (1:1 molar ratio of Ru precursor to KOH) exhibits ultralow overpotential of 34 mV for HER and oxidation potential of −56 mV versus the reversible hydrogen electrode for HzOR at a current density of 10 mA⸱cm⁻² in alkaline media. In overall hydrazine splitting, a symmetric Ru/RuO₂-1||Ru/RuO₂-1 pair achieves current densities of 10 and 150 mA⸱cm⁻² at ultralow cell voltages of 0.044 and 0.717 V, respectively. Furthermore, a Zn–hydrazine battery assembled with Ru/RuO₂-1 as the cathode enables self-powered hydrogen generation with stable operation for 200 h. Advanced in situ and ex situ spectroscopies combined with density functional theory reveal that strong electronic coupling at the Ru/RuO₂ interface promotes intermediate adsorption and lowers kinetic barriers for both the HER and HzOR. This study introduces a CO₂ laser-induced interfacial engineering strategy for designing advanced electrocatalysts for self-powered and energy-efficient H₂ production technologies.