Ag-doped Ag 2 S@MoS 2 catalyst for alkaline hydrogen evolution reaction

In this paper, a hydrothermal synthesis method synthesized a foamed nickel (NF)-supported Ag-doped Ag 2 S@MoS 2 hydrogen evolution catalyst. Silver doping can improve the conductivity of MoS 2 , thereby improving the hydrogen evolution activity of MoS 2 . Compared with a single MoS 2 , the Ag 2 S@MoS 2 electrode has a larger specific surface area and has many highly catalytic S edges. In 1 M KOH, the overpotential of Ag 2 S@Ag 0.33 MoS 2 /NF electrode at 10 mA cm −2 is approximately 188 mV. Comparing with the overpotential of NF (391 mV) and MoS 2 /NF (290 mV), it is much lower. Further changing the amount of silver added, the overpotential of Ag 2 S@Ag 0.5 MoS 2 /NF is further reduced to 165 mV at a current density of 10 mA cm −2 . When the voltage is 0.35 V, the current densities of Ag 2 S@Ag 0.33 MoS 2 /NF (42.45 mA cm −2 ) and Ag 2 S@Ag 0.5 MoS 2 /NF (55.5 mA cm −2 ) are higher than those of NF (4.91 mA cm −2 ) and MoS 2 /NF (20.51 mA cm −2 ).