Preparation and Hydrogen Evolution Performance of Porous Ni-Cr-Mo-Cu Phosphating Electrode

In search for an efficient and low cost electrode material, porous Ni-Cr-Mo-Cu phosphating electrode was prepared by powder metallurgy and low temperature phosphating method. The phase, morphologic structure, and element distribution of the electrode were characterized by X-ray diffraction analysis (XRD), scanning electron microscope (SEM), and X-ray energy spectrum analysis (EDS). The electrocatalytic hydrogen evolution properties of phosphide electrode materials were tested by open-circuit potential (OCP), linear polarization curves (LSV) and electrochemical impedance spectrum (EIS). The results show that the porous Ni-Cr-Mo-Cu phosphating electrode exhibits excellent hydrogen evolution performance, which could be optimized by adjusting the phosphating time. At room temperature, the porous Ni-Cr-Mo-Cu phosphating electrode with a phosphating time of 2 h exhibits a good hydrogen evolution performance in a solution of 6 mol/L KOH, and its hydrogen evolution overpotential is only –0.19 V (vs RHE). When the exchange current density is 10 mA/cm2, the corresponding polarization potential is –0.20 V (vs RHE). After 18 000 s of OCP test, the potential of the electrode material decreases by only 0.02 V (from +0.80 to +0.78 V (vs RHE)), which indicates that the electrode material has good chemical stability. © 2022 Rare Metals Materials and Engineering Press. All rights reserved.