Synergy Between Ru 3 Nanoclusters and Pt Nanoparticles for High‐Efficiency Alkaline Hydrogen Evolution Reaction

ABSTRACT To achieve efficient alkaline hydrogen evolution reaction (HER), catalysts should be rationally designed with optimized water adsorption energy, low H‐OH dissociation energy barrier, and appropriate hydrogen bond energy (HBE). However, simultaneously satisfying these requirements remains a major challenge for single‐component catalysts. Here, we report a dual‐site synergistic catalyst composed of atomically precise Ru 3 nanoclusters and Pt nanoparticles (Ru 3 @Pt NPs/C). Characterization results reveal Ru 3 nanoclusters are distributed around Pt nanoparticles. Compared with single‐component catalyst, Ru 3 @Pt NPs/C exhibits superior catalytic activity, achieving a current density of 10 mA cm −2 at an ultra‐low overpotential of only 10 mV, and the mass activity reached 0.488 A mg −1 PGM , which was 1.85 times that of commercial Pt/C (0.264 A mg −1 PGM ). Furthermore, Ru 3 @Pt NPs/C exhibits a low cell voltage of 1.75 V at 1 A cm −2 in the anion exchange membrane electrolyzer. Density functional theory (DFT) calculations reveal its superior performance stems from a relay catalytic mechanism: water molecules are preferentially adsorbed and dissociated at Ru site, while the generated *H rapidly migrate to neighboring Pt sites, where they efficiently recombine to form H 2 . This study proposes an innovative dual‐component catalytic architecture that integrates triatomic clusters with nanoparticles, providing new perspectives for atomic‐scale design of advanced catalysts.