Ni3S2@MoO3 core/shell arrays on Ni foam modified with ultrathin CdS layer as a superior electrocatalyst for hydrogen evolution reaction.

An ultrathin CdS layer-modified MoO3/Ni3S2 hierarchical nanoarray on Ni foam exhibits ultrahigh electrocatalytic activity towards the hydrogen evolution reaction with a small overpotential of 30 mV at -10 mA cm-2 due to the synergistic effect of easy electron transfer among CdS, MoO3 and Ni3S2/NF and the well-designed structure, which outperforms the current non-noble electrocatalysts.