Electrodeposition of amorphous molybdenum sulfide thin film for electrochemical hydrogen evolution reaction.

Amorphous molybdenum sulfide (MoS) is a highly active noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER). The MoS was prepared by electrochemical deposition at room temperature. Low-cost precursors of Mo and S were adopted to synthesize thiomolybdates solution as the electrolyte. It replaces the expensive (NH)MoS and avoid the poison gas (HS) to generate or employ. The (MoOS), (MoOS) and (MoS) ions were determined by UV-VIS spectroscopy. The electrodeposition of MoS was confirmed with XRD, XPS and SEM. The electrocatalyst activity was measured by polarization curve. The electrolyte contained (MoOS) ion and (MoOS) ion electrodeposit the MoS thin film displays a relatively high activity for HER with low overpotential of 211 mV at a current density of 10 mA cm, a relatively high current density of 21.03 mA cm at = 250 mV, a small Tafel slope of 55 mV dec. The added sodium dodecyl sulfate (SDS) can efficient improve the stability of the MoS film catalyst.