Atomically Dispersed Ni on Nitrogen‐Doped Carbon Substrate Enhances Basic HER Performance of Ru Clusters**

Abstract Hydrogen production through water electrolysis is a viable method to reduce reliance on conventional energy sources. Nonetheless, water electrolysis necessitates using effective electrocatalysts to enhance the efficiency of converting electrical energy into chemical energy. Compared with the high cost of platinum (Pt), ruthenium (Ru)‐based materials show significant promise as electrocatalysts for the hydrogen evolution reaction (HER). Here, a Ru cluster supported on a nitrogen‐doped carbon substrate containing an atomically dispersed nickel electrocatalyst is synthesized (NiRu‐NC). In NiRu‐NC electrocatalyst, Ru clusters act as primary active sites, while atomically dispersed Ni atoms act as auxiliary sites. The HER activity of Ru clusters is enhanced by modifying the electronic structure of Ru sites. This unique structure enhances the interaction between the Ru cluster and the substrate, showing excellent HER performance in an alkaline environment. The overpotential at 10 mA cm −2 is only 25 mV, and the Tafel slope is 29 mV dec −1 . In continuous operation for 24 h, the overpotential value hardly rose, indicating exemplary stability behavior of the applied NiRu‐NC electrocatalyst.