Promoted alkaline hydrogen evolution by an N-doped Pt–Ru single atom alloy

Abstract

Since water dissociation and H desorption kinetics essentially determine the performance of the alkaline hydrogen evolution reaction (HER), rationally regulating surface adsorption behavior to achieve a superior catalytic surface is always challenging for catalysts. Herein, N-doped Pt–Ru single atom alloy electrocatalysts were constructed by dispersing diluted Pt single atoms onto Ru nanoparticles by thermal annealing in an ammonium atmosphere. The prepared (Ru–N)@Pt can substantially boost the alkaline HER catalysis of Ru nanoparticles and deliver an impressive overpotential of only 15 mV at 10 mA cm⁻². X-ray-absorption fine structure characterization confirms that the doped N species have bonding interaction with both Ru and Pt sites. Theoretical calculations reveal that N incorporation helps strengthen the interfacial interaction between H₂O and Ru sites by precise orbital engineering, while the Pt sites facilitate the H₂ desorption kinetics. This work not only provides an effective strategy to construct single atom alloy electrocatalysts for a high-performance alkaline HER, but also sheds light on the understanding of the reaction mechanism at the atomic level.