RhMoS₂ Nanocomposite Catalysts with Pt-Like Activity for Hydrogen Evolution Reaction

High overpotentials and low efficiency are two main factors that restrict the practical application for MoS₂, the most promising candidate for hydrogen evolution catalysis. Here, RhMoS₂ nanocomposites, the addition of a small amount of Rh (5.2 wt%), exhibit the superior electrochemical hydrogen evolution performance with low overpotentials, small Tafel slope (24 mV dec⁻¹), and long term of stability. Experimental results reveal that 5.2 wt% RhMoS₂ nanocomposite, even exceeding the commercial 20 wt% Pt/C when the potential is less than −0.18 V, exhibits an excellent mass activity of 13.87 A mg_metal ⁻¹ at −0.25 V, four times as large as that of the commercial 20 wt% Pt/C catalyst. The hydrogen yield of 5.2 wt% RhMoS₂ nanocomposite is 26.3% larger than that of the commercial 20 wt% Pt/C at the potential of −0.25 V. The dramatically improved electrocatalytic performance of RhMoS₂ nanocomposites may be attributed to the hydrogen spillover from Rh to MoS₂.