Preparation Of Nickel-based Electrocatalytic Nanomaterials By Dealloying Method And Its Water Splitting Performance

With the progress of human society,energy and environmental issues have become two major issues facing scientific development today.Among them,hydrogen energy is a new type of non-polluting energy and has broad application prospects.However,it is difficult to obtain hydrogen energy because of its high cost.Hydrogen production from water splitting is a method with high purity and simple operation,but it also has the problems of high energy consumption and low conversion efficiency.Therefore,stable and efficient electrocatalysts have attracted increasing attention from experts and scholars in this field.And the self-activation characteristics of transition metal oxide（TMO）can enhance the molecular dynamics of the material in complex water splitting process.In this paper,a cheap and efficient nickel-based electrode catalyst is prepared by a simple method.Specifically divided into the following studies:1.Using thin nickel sheets as substrates,NiOx nanostructure films were prepared by electrochemical co-deposition and dealloying methods,and Co₃O₄ films were deposited on NiOx nanosheets by atomic layer deposition（ALD）.After annealing,Ni Co₂O₄ nanostructure films were formed.The study found that the electrochemical analysis in 1M Na OH showed that the composite nanosheets had a low overpotential at a current density of 10 m A/cm² is 315m V.Ni Co₂O₄ belongs to the spinel structure.Under the action of Co²⁺/Co³⁺and Ni²⁺/Ni³⁺electron pairs,the charge transfer is more and the activity is greater.2.Using a hydrothermal vulcanization method,Ni₃S₂ nanorods（NRs）with a small volume and a large number were prepared on a nickel sheet substrate.Next,a large number of defects are generated in the crystal lattice through vacancy control,thereby obtaining a metal sulfide nanocatalyst with sulfur vacancies,and having excellent catalytic activity and chemical stability.The overpotential of the catalyst in a 1M Na OH solution at a current density of 10 m A/cm² is only 162 m V.The performance test and calculation results show that the synergistic reaction caused by the electron-hole transfer guided by sulfur vacancies promotes the Volmer reaction.It significantly improves the HER catalytic efficiency of Ni₃S₂ NRs.3.The nickel sulfide doped P with sulfur vacancy in content 2 was investigated by vacuum heat treatment and gas phase reduction deposition.The results show that the doping of element P significantly improves its conductivity and catalytic performance in the hydrogen evolution reaction by increasing the electron attraction of the catalyst.