LAUSR

Abstract In order to achieve cost-effective hydrogen production, the development of efficient and stable electrocatalysts for alkaline water splitting has aroused wide attention recently. Here, Ni2P nanosheets arrays decorated with ruthenium nanoparticles are grown in situ on a carbon cloth substrate (denoted as Ru-Ni2P/CC) via surface modification engineering, exhibiting good electrical conductivity and superior hydrophilicity. The resulting Ru-Ni2P/CC-5 with Ru content of 8.98 wt.% exhibits an ultra-low overpotential of only 23 mV to achieve a current density of 10 mA cm-2 for hydrogen evolution reaction (HER) and good long-term stability in alkaline solution. The corresponding X-ray photoelectron spectroscopy characterization displays the strong electron interaction between Ru and Ni2P, which facilitates the regulation of their internal electron configuration. Density functional theory calculations reveal that the Ni sites in Ni2P nanosheets are conducive to the dissociation of water molecules owing to lower energy barrier, while Ru sites act as catalytic active center for the production of molecular hydrogen. The present work offers a reasonable design route of efficient electrocatalyst for HER in alkaline solution.