D‐Orbital‐Modulated Ruthenium Embedded within Functionalized Hollow MXene Networks for Enhanced Hydrazine‐Assisted Hydrogen Production

Abstract Electrochemical green hydrogen production via water splitting is an attractive and sustainable pathway; however, the sluggish kinetics of anodic oxygen evolution reaction is still a critical challenge. In this study, an effective electrocatalyst engineering approach is demonstrated by preparing an innovative hybrid of ruthenium d‐orbitals‐regulated nanoclusters embedding within functionalized hollow Ti 3 C 2 MXene networks (Ru 0.91 Ni 0.09 ‐N/O‐Ti 3 C 2 ) to promote the hydrazine‐assisted hydrogen production. A specific charge redistribution is revealed, locally concentrating at interfaces derived from stable Ru(Ni)‐N/O‐Ti coordination and d – p orbital hybridization. The charge transfer effect from Ni to Ru within Ru 0.91 Ni 0.09 structure and Ru 0.91 Ni 0.09 to N/O‐Ti 3 C 2 tailors electronic features of Ru sites to enable reasonable adsorption/desorption toward reactant intermediates. The Ru 0.91 Ni 0.09 ‐N/O‐Ti 3 C 2 requires an overpotential of only 29.3 mV for cathodic hydrogen evolution and a low potential of −29.9 mV for anodic hydrazine oxidation to reach 10 mA cm −2 , showing excellent stability. The hydrazine‐assisted hydrogen production system based on Ru 0.91 Ni 0.09 ‐N/O‐Ti 3 C 2 electrodes delivers small cell voltages of 0.02 V at 10 mA cm −2 and 0.92 V at industrial current level of 1.0 A cm −2 . This work may open a new electrocatalysis strategy from lab scale to industry for robust and efficient green hydrogen production.