Amorphous ruthenium nanosheets for efficient hydrazine-assisted water splitting

The hydrazine oxidation reaction (HzOR) has garnered significant attention as a feasible approach to replace sluggish anodic reactions to save energy. Nevertheless, there are still difficulties in developing highly efficient catalysts for the HzOR. Herein, we report amorphous ruthenium nanosheets (a-Ru NSs) with a thickness of approximately 9.6 nm. As a superior bifunctional electrocatalyst, a-Ru NSs exhibited enhanced electrocatalytic performance toward both the HzOR and hydrogen evolution reaction (HER), outperforming benchmark Pt/C catalysts, where the a-Ru NSs achieved a working potential of merely −76 mV and a low overpotential of only 17 mV to attain a current density of 10 mA cm⁻² for the HzOR and HER, respectively. Furthermore, a-Ru NSs displayed a low cell voltage of 28 mV at 10 mA cm⁻² for overall hydrazine splitting in a two-electrode electrolyzer. In situ Raman spectra revealed that the a-Ru NSs can efficiently promote N‒N bond cleavage, thereby producing more *NH₂ and accelerating the progress of the reaction.