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 H2desorption 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.