Electrocatalytic Hydrogen Evolution Properties of Nanocrystalline Ni-W-Fe-La Alloy Coating by Pulse Electrodeposition

The nanocrystalline Ni-W-Fe-La alloy coating was prepared by pulse electrodeposition and then the coating was heat-treated under the protection of Ar.The morphology and phase composition of the coating were analyzed by means of SEM and XRD.The electrocatalytic properties for hydrogen evolution reaction (HER)of the coatings under different states were studied through polarization curves,cyclic voltammetry curves and electrochemical impedance spectroscopy.The results indicate that the grains of the coating surface distributed uniformly and closely with no cracks.The microstructure was substitutional solutes with Ni as the solvent and W and Fe as the solute.The coatings of the alloy had the best hydrogen evolution properties after heat treatment at 200 ℃ for 60 min.In comparison with the traditional iron electrode,the potential for hydrogen evolution was positively shifted about 250 mV.