Revealing the Role of Ru-O-Ce Interface Coupling in CeO₂-Ru Aerogel for Boosting Hydrogen Evolution Kinetics

Designing heterogeneous interface to enhance the kinetics for electrocatalysts is a highly efficient but challenging pathway toward hydrogen evolution reaction (HER) in water electrolysis. Herein, the heterogeneous coupling of CeO₂ quantum dots onto porous Ru aerogel through interfacial Ru-O-Ce bridge is proposed to construct CeO₂-Ru aerogel as the superior HER electrocatalyst with ultra-low overpotentials. In situ characterizations and theoretical calculations reveal the electron distribution at the heterogeneous Ru-O-Ce bridge to boost hydrogen bonding at Ru sites, and the faster water adsorption and dissociation at the CeO₂ sites to enhance the HER kinetics. Furthermore, CeO₂-Ru aerogel is employed as excellent cathodes for both acidic and alkaline water electrolyzers with ampere-level current density and stably operated over 500 hours. Thus, the synergistic effect for CeO₂-Ru aerogel through the Ru-O-Ce bridge tunes the HER catalytic mechanism and reinforces the activity, realizing highly efficient hydrogen generation in water electrolysis.