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.