Preparation of Cu-Ni-Mo Ternary Electrode by Electrodeposition and Its Hydrogen Evolution Performance

One step DC electrodeposition double-sided plating is an electrodeposition method that can obtain double-sided coated electrodes. The work aims to prepare a porous hydrogen evolution cathode material with high hydrogen desorption activity and stability. Nickel molybdenum binary alloy has good hydrogen evolution performance because of its "synergistic effect", but it also has the problem of component dissolution in the electrolysis process. The formation of Cu-Ni bimetallic catalyst has strong synergistic effect, and its ability to destroy O-H bond is strong, which is conducive to the electrocatalytic process of HER in alkaline solution. By combining the advantages of the two binary alloys, the hydrogen evolution performance of the electrode is improved. This study introduced the preparation of a nickel based hydrogen evolution cathode material with high efficiency, low cost and high stability in alkaline solution. The experiment was conducted at 35 ℃ through the three-electrode system with two anode plates (graphite) and with the foam nickel as the cathode. The two anode plates were on the left and right sides of the foam nickel, and the area was slightly larger than that of the foam nickel. Cu-Ni and Cu-Ni-Mo coatings were deposited on the surface of foam nickel (NF) by one-step DC electrodeposition Cu-Ni/NF Binary hydrogen evolution electrode, Cu-Ni-Mo/NF Ternary hydrogen evolution electrode. The surface morphology, content of structural elements and phase of the electrode were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The hydrogen evolution performance and catalytic activity of the electrode were characterized by electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV) and cyclic voltammetry (CV). The test results showed that compared with the binary coating, Mo doping existed in the form of displacement solid solution in the alloy structure, which increased the lattice constant of the coating. In terms of the electrochemical performance of Cu-Ni-Mo/NF, at a current density of 10 mV/cm2, the over potential of the ternary electrode was only 116 mV, the Tafel slope was 104 mV/dec, the charge transfer resistance was 15.34 Ω, and the electrochemical active specific surface area (ECSA) was 22.33. Compared with Cu-Ni/NF, the binary electrode decreased by 68 mV, 27 mV/dec, 15.48 Ω, and the ECSA value increased by 7.95. After 2 000 cycles of CV cycle, the hydrogen evolution overpotential changed little, showing good hydrogen evolution stability. Analysis of the test results can be found that when the third element Mo is introduced, the coating morphology of the Cu-Ni binary electrode is changed, the grains are refined, and the spherical cell structure formed by the close accumulation of particles, so as to improve the specific surface area of the electrode material, provide more active sites for hydrogen evolution reaction, and help to improve the efficiency of hydrogen evolution reaction. Due to the synergistic effect between the three metals, Cu-Ni-Mo ternary electrode shows better HER catalytic performance than Cu-Ni binary electrode. Therefore, Cu-Ni-Mo ternary electrode is a good HER electrocatalyst. In the process of production and preparation, it does not produce adverse by-products to environmental protection, and can be produced in batch, which is of great significance to its promotion and market application. © 2023 Chongqing Wujiu Periodicals Press. All rights reserved.