Enhanced interface interaction in Cu2S@Ni core-shell nanorod arrays as hydrogen evolution reaction electrode for alkaline seawater electrolysis

Abstract

Exploring cheap, efficient and stable electro-catalysts for hydrogen evolution reaction (HER) is a vital technology for seawater splitting development. Herein, we demonstrate that constructing underlying Cu2S nanorod arrays is crucial for improving the HER activity of surface Ni catalyst. Electrochemical results reveal that nickel coated Cu2S nanoarrays (Cu2S@Ni) on copper foam exhibits a preferable HER activity (~500 mA cm−2 at <200 mV overpotential), outperforming Cu2O@Ni and pure Ni counterparts. Detailed analyses indicate that the enhanced HER activity of Cu2S@Ni can be attributed to Ni–S interaction between surface nickel and underlying Cu2S nanorods, which optimizes the adsorption energy of hydrogen on the surface. Moreover, the Cu2S@Ni nanoarray electrode shows a remarkable HER stability, highlighting its promising potential in alkaline seawater electrolysis.