Strong metal–support interaction boosts the electrocatalytic hydrogen evolution capability of Ru nanoparticles supported on titanium nitride

Abstract Ruthenium (Ru) has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction (HER), owing to its inherent high activity and being the cheapest platinum‐group metal. Herein, based on the idea of strong metal–support interaction (SMSI) regulation, Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated, which were applied to the alkaline electrolytic water. Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased. Further study shows that the exposed Ru–TiN interfaces greatly promote the H₂ desorption capacity. Thus, the Ru/TiN‐300 with a moderate SMSI degree exhibits excellent HER performance, with an overpotential of 38 mV at 10 mA cm⁻². Also, due to the encapsulation role of TiN overlayer on Ru nanoparticles, it displays super long‐term stability with a very slight potential change after 24 h. This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering.