Thermal Shock Synthesis for Loading Sub‐2 nm Ru Nanoclusters on Titanium Nitride as a Remarkable Electrocatalyst toward Hydrogen Evolution Reaction

Abstract Heterogeneous catalysts embracing metal entities on suitable supports are profound in catalyzing various chemical reactions, and substantial synthetic endeavors in metal–support interaction modulation are made to enhance catalytic performance. Here, it is reported the loading of sub‐2 nm Ru nanocrystals (NCs) on titanium nitride support (HTS‐Ru‐NCs/TiN) via a special Ru–Ti interaction using the high‐temperature shock (HTS) method. Direct dechlorination of the adsorbed RuCl₃, ultrafast nucleation process, and short coalescence duration at ultrahigh temperatures contribute to the immobilization of Ru NCs on TiN support via producing the Ru–Ti interfacial perimeter. HTS‐Ru‐NCs/TiN shows remarkable activity toward hydrogen evolution reaction (HER) in alkaline solution, yielding ultralow overpotentials of 16.3 and 86.6 mV to achieve 10 and 100 mA cm⁻², respectively. The alkaline and anion exchange membrane water electrolyzers assembled using HTS‐Ru‐NCs/TiN yield 1.0 A cm⁻² at 1.65 and 1.67 V, respectively, which validate its applicability in the hydrogen production industry. Theoretical simulations reveal the favorable formation of Ru─O and Ti─H bonds at the interfacial perimeters between Ru NCs and TiN, which accelerates the prerequisite water dissociation kinetics for enhanced HER activity. This exemplified work motivates the design of specific interfacial perimeters via the HTS strategy to improve the performance of diverse catalysis.