Study On The Fabrication Of Nickle-based Alloy Electrodes And Its Catalytic Performance For Hydrogen Evolution

Hydrogen is a well-recognized ideal energy source with high efficiency and cleanliness.Electrolysis water for hydrogen production is an important means of industrial production of hydrogen.It has positive and profound influence to study and develop low cost,low overpotential,high electrolytic stability and excellent catalytic performance cathode materials for hydrogen evolution in a large-scale industrialization.In this thesis,Ni-Mo alloy electrodes were prepared by electrodeposition method.Then on the base of these,Ni-Mo-S alloy electrodes were synthesized by hydrothermal method.By optimizing the process conditions and comparing the electrochemical performance of the electrodes,the best experimental preparation methods had determined,which could provide new ideas for the design and preparation of high performance energy conversion and storage materials in the future.The details of this dissertation are summarized briefly as follows:1.The best experimental scheme of Ni-Mo alloy electrode prepared by electrodeposition method is as follows: the concentration of nickel sulfate is 0.1 mol/L,the concentration of sodium citrate is 0.25 mol/L,the concentration of sodium molybdate is 0.05 mol/L,the concentration of sodium chloride is 0.3 mol/L,the p H value of the plating solution is 9.7,the electrodeposition current density is 32 m A/cm2,the bath temperature is 30 ℃,the stirring speed is 1200 rad/min,the electroplating time is 60 min.The electrochemical test results of Ni-Mo alloy electrode in 1 mol/L Na OH solution at 25 ℃ showed that the hydrogen evolution overpotential of Ni-Mo alloy electrode was about 200 m V lower than that of pure Ni electrode when the current density was 10 m A/cm2,And had high electrochemical stability.The surface morphology of the Ni-Mo electrodeposited coating was observed to be rough with many small cracks.The elemental composition and structure of the coating were characterized by EDX and XRD.It was found that when the content of Mo was 23 at%,the catalytic hydrogen evolution performance of the Ni-Mo alloy electrode was the best.When Mo element was added to the coating,it showed the trend of amorphization,the electrode surface area increased,and the catalytic hydrogen evolution performance would be greatly improved.2.Based on the preparation of Ni-Mo alloy by electrodeposition,the Ni-Mo-S alloy electrodes were synthesized by hydrothermal method and the optimum process conditions were determined.The experimental results showed that when the current density was 10 m A/cm2,the hydrogen evolution overpotential of Ni-Mo-S alloy electrode was about 35 m V lower than that of Ni-Mo alloy electrode,about 235 m V lower than pure Ni electrode,and the electrochemical stability was further improved.The surface morphology of Ni-Mo-S alloy electrodeposits showed more fine particles and cracks.When the content of S was 5.7 at%,the catalytic hydrogen evolution performance of Ni-Mo-S alloy electrode was the best.The addition of S element further increased the tendency of the coating to be amorphized,decreased the grain size of the coating and greatly increased the catalytic hydrogen evolution performance of the Ni-Mo-S alloy electrode.