Restructuring Hydrogen Bond Networks and Enhancing Dehydrogenation Kinetics for Efficient Hydrazine Oxidation‐Assisted Electrolytic Hydrogen Production

ABSTRACT Hydrazine‐assisted water electrolysis provides a viable route toward energy‐conservative hydrogen generation while simultaneously addressing the environmental concerns associated with hazardous hydrazine pollutants. Herein, Ru nanoparticles are anchored onto Fe‐NiMoO 4 hollow nanorods through an etching and solvothermal method, resulting in the formation of Ru/Fe‐NiMoO 4 as a dual‐functional electrocatalyst for both the hydrogen evolution reaction (HER) and the hydrazine oxidation reaction (HzOR). Studies indicate that the introduction of Fe alters the electronic properties around the active species Ru, which alters the electronic properties of the catalyst and optimally tunes the d‐band center of Ru/Fe‐NiMoO 4 to an optimal position. This modification balances the adsorption and desorption of H* at each metal active site and enhances the reaction kinetics of the corresponding hydrazine dehydrogenation. For HER and HzOR, only −167 and 37 mV working potentials are required to achieve 1000 mA cm −2 , respectively. Notably, when Ru/Fe‐NiMoO 4 is employed as both the cathode and anode in an overall hydrazine‐assisted water splitting (OHzS) system, attaining 500 mA cm −2 with an exceptionally low cell potential of 0.23 V, while maintaining stable operation for over 100 h. Additionally, the assembled direct liquid N 2 H 4– H 2 O 2 fuel cell (DHHPFC) delivers a maximum power density of 336 mW cm −2 at 80°C. This work opens new avenues for efficient hydrogen production through hydrazine‐assisted processes.