Boosting the Performance Gain of Ru/C for Hydrogen Evolution Reaction Via Surface Engineering

The surface properties of catalysts determine the intrinsic activity and adaptability. Ruthenium is regarded as a potential candidate to substitute platinum for water electrolysis due to the low cost and analogous electronic structures while it suffers from severe dissolution and stability problems. Herein, the modification of Ru/C with atomically dispersed cobalt atoms is achieved via a simple thermal doping method. The newly formed amorphous shell with Ru-Co sites on the Ru/C catalyst improved the hydrogen evolution reaction activity and stability significantly. Impressively, the obtained Co₁Ru@Ru/CN_x catalyst exhibited an overpotential as low as 30 mV at 10 mA cm⁻² in an alkaline medium, which is among the best HER catalysts reported so far. The oxygen oxophile Co prevents the fast oxidation and dissolution of Ru species, ensuring outstanding long-term durability up to 70 h. Theoretical calculations reveal that the Ru-Co coordination acts as a more active site for water dissociation than the Ru-Ru. Meanwhile, the “Ru-Co shell/Ru core” structures show high adaptability for the reaction conditions. This simple doping strategy offers prospects for scalable preparation of highly active electrocatalysts.