Holes to nanoparticles grafting configuration: The oxygen vacancy-RuP₄ configuration exerts a grafting effect on...

Supported catalysts with traditional heterostructures are often limited by weak interfacial effects caused by lattice mismatches, leading to reduced electrode efficiencies and rapid deactivation. Inspired by the ability of plant cutting surfaces to graft multiple species and the superstability of the resulting structures, quenching-derived oxygen vacancies (O_v) on MoO_2-x nanorods were utilized herein to anchor Ru species and facilitate the formation of RuP₄ nanoparticles tightly grafted onto the MoO_2-x surfaces. Unlike conventional heterostructures, this distinctive O_v-RuP₄ grafting architecture enhances interfacial electron transfer, thereby inducing a strong grafting effect. This configuration optimizes the reactant affinity of Mo sites adjacent to O_v as well as Ru active sites while improving structural stability under industrial-grade current densities. Density functional theory (DFT) calculations reveal that Mo vacancy sites exhibit enhanced hydrophilicity and *OH binding, whereas Ru sites exhibit optimal *H adsorption performance, collectively accelerating hydrogen evolution reaction (HER) kinetics. As a result, the mass activity of RuP₄@MoO_2-x (at 0.1 V) reaches 8309 and 1842.4 mA mg_Ru^-1 for the alkaline and acidic HER, respectively, considerably surpassing those of RuP₄@MoO₂ and Pt/C. Furthermore, RuP₄@MoO_2-x maintains ultralow Ru leaching and superior structural stability during HER operation under industrial-grade current densities. Overall, this work introduces a grafting-inspired strategy for supported catalyst design by leveraging defect engineering, providing a new direction for developing industrial-scale electrodes.