Laser Irradiation Induced Ru Cluster‐Based Catalysts with Dual Spillover Pathways for Alkaline Hydrogen Evolution

Abstract Ru cluster‐based electrocatalysts are promising for alkaline hydrogen evolution reaction (HER). However, the strong adsorption of H* and OH* intermediates during water dissociation on these clusters severely hampers subsequent gas evolution. Herein, we report a rational design of Co(OH) x ‐supported Ru clusters (L‐Ru/Co(OH) x ) through laser irradiation featuring dual spillover pathways for H* and OH*. The laser irradiation induces a localized thermal effect with fast heating and quenching, which simultaneously generates uniformly dispersed oxygen vacancies (OVs) on Co(OH) x nanosheets and forms ultrafine Ru clusters that are directly anchored at the OVs. The L‐Ru/Co(OH) x enables a synergistic electron redistribution among Ru clusters, OVs, and the adjacent Co sites, yielding electron‐rich Ru and Co sites along with electron‐deficient OVs. Such electron modulation facilitates spillover of H* and OH* on the Ru clusters to the adjacent electron‐rich Co sites and OVs, respectively, promoting continuous hydrogen evolution. The optimal catalyst exhibits a low overpotential of 13 mV at 10 mA cm −2 and a Tafel slope of 42 mV dec −1 , outperforming most reported catalysts. When used in an anion exchange membrane electrolyzer, the device achieves an industrial‐level current density of 1.68 A cm −2 at 2.0 V, which is about 2.16 times higher than that on RuO 2 ||Pt/C benchmark.