Preparation Of Ni-co Alloy Composite MoS₂ Porous Electrode And Study On Hydrogen Evolution Properties

In order to reduce the cost and energy consumption of non-precious metal electrode materials,Ni-Co-Zn/MoS₂ composite electrode was prepared on the surface of Cu substrate by pulse electrodeposition.Finally,Ni-Co/MoS₂ porous composite electrode was prepared by alloying at 70°C 6 mol/L NaOH solution.Cyclic voltammetry,ac impedance spectroscopy and chronoamperometry were used to study the effect of pH and sodium citrate on the electrodeposition behavior of Ni-Co-Zn and the effect of Zn and MoS₂ on the electrodeposition behavior of Ni-Co.As the pH increases,the deposition of Ni-Co-Zn is inhibited,especially at pH 7 and 8,the reduction potential is largely negatively shifted.The change of the pH value of the electrolyte causes the nucleation rate to change.The increase of cit increases the reduction inhibition of metal ions,resulting in the nucleation of Ni-Co-Zn by two-dimensional nucleation and three-dimensional nucleation in series to two-dimensional nucleation.Ni,Co and Zn have abnormal co-deposition.Although the addition of Zn delays the deposition of Ni-Co,the nucleation of Ni-Co changes from continuous nucleation to transient nucleation.MoS₂ is added to the electrolyte,the reaction form of the metal ions is not changed,but the electrochemical reduction reaction is inhibited by the MoS₂.MoS₂ is added to promote the electrocrystallization process of Ni-Co,which completely transforms the nucleation process into instantaneous three-dimensional nucleation.As the overpotential increases,the nucleation rate increases.The morphology and roughness of Ni-Co/MoS₂ composite porous electrode under different process parameters were characterized by SEM and LSCM.The HER of the Ni-Co/MoS₂ composite porous electrode were analyzed by cathodic polarization curves and electrochemical impedance spectroscopy.The results show that the optimum process parameters for the preparation of Ni-Co/MoS₂ composite porous electrode materials were obtained.The pH value was 6,the average current density was 5 A·dm^-2,the duty ratio was 0.2,and the bath temperature was 40°C.Figure 39;Table 22;Reference 65.