Enhanced Tri-Atom Ru-Based Catalyst for Hydrogen Evolution Reaction via Rapid Pyrolysis of Precursor

Abstract

Atomically precise supported nanocluster catalysts (APSNCs), with well-defined metal active sites, unique geometrical and electronic structures and metal–metal bonds, demonstrate excellent catalytic performance. However, the synthesis of APSNCs with well-defined active centers and stable structures remains a huge challenge due to uncontrollable aggregation during synthesis and catalytic reactions. Herein, the Ru₃ nanocluster catalysts uniformly dispersed on oxidized carbon nanotubes (Ru₃/OCNT) is successfully synthesized by using a rapid pyrolysis of precursor strategy. The obtained Ru₃/OCNT exhibits excellent catalytic performance for alkaline hydrogen evolution reaction (HER). The catalyst achieves an overpotential of 19 mV at a current density of 10 mA cm⁻² in 1 m KOH solution, outperforming commercial 20 wt.% Pt/C and 5 wt.% Ru/C. Moreover, the mass activity of Ru₃/OCNT is 23.47 and 11.83 times higher than that of commercial Pt/C and Ru/C. Density functional theory (DFT) calculations reveal that the metal–metal interaction and metal–support interaction in Ru₃/OCNT effectively modulate the electronic structure of Ru atoms, lower the hydrogen adsorption energy of the catalytic site, and promote the H* desorption. This work offers a new perspective on the design and synthesis of APSNCs with excellent alkaline hydrogen evolution performance.