Hydrogen Evolution Properties Of Nanoporous Ni-M(Fe,Cu,Co) Alloy Prepared By Dealloying

With the development of economic,The consumption of fossil fuel has speed up growth,caused by environmental problems,smog,acid rain,greenhouse effect etc,has the serious influence people's normal life.Search for a new,applied widely,renewable energy has become a problem to be solved.Hydrogen is the most element on earth,and has the advantages of abundant,no pollution,recycled etc.Therefore,the development and utilization of hydrogen energy is of great significance.At present the preparation of hydrogen mainly use the method of electrolysis of water.However,the hydrogen production efficiency by electrolysis of water is not high.Hydrogen evolution overpotential of the electrode material is too high,caused waste of energy,restricting the development of hydrogen production by electrolysis of water.Therefore,the preparation of low hydrogen evolution overpotential,stable and low-cost efficient cathode materials is of great significance.Vacuum smelting and solid solution treatment prepare different alloy elements of Ni-Fe-Mn alloy,including Ni30Mn70 alloy consisting of a single Mn phase,and Ni20Fe10Mn70 and Ni10Fe20Mn70 alloy consisting of a single Fe3Mn7 phase.The content of Fe has a significant influence on nanoporous structure.Through hydrogen evolution performance test and analysis,found that the addition of Fe increases the surface area,reducing hydrogen evolution overpotential and improving the stability of the electrode.Under the current density of 0.15 A·cm-2,hydrogen evolution overpotential of nanoporous Ni-Fe alloy by Ni20Fe10Mn70 is 154 m V,and at a current density of 0.1 A·cm-2,the alloy electrode exhibits good electrochemical stability over a long period of continuous electrolysis.Alloy composition have a significant impact on the formation of the nanoporous structure,this conclusion also applies to Ni-Cu-Mn alloy,Ni20Cu10Mn70 and Ni10Cu20Mn70 composed by a single Cu Mn4 phase,the nanoporous structure different from each other,and the difference is bigger with the nanometer porous Ni,which is formed by the Ni30Mn70,Ni20Cu10Mn70 obtains the structure of nanoporous structure with the "fold" nanosheet to provide more active sites for the hydrogenation reaction.Based on the formation of the nanoporous Ni-Cu alloy,hydrogen evolution of performance test and analysis,found that formed nanoporous Ni-Cu by Ni20Cu10Mn70 has better performance of hydrogen evolution.Under the current density of 0.15 A·cm-2,hydrogen evolution overpotential is 195 m V,and at 0.1 A·cm-2 current density,the alloy electrode exhibits good electrochemical stability over a long period of continuous electrolysis.Ni20Co10Mn70 precursor phase composition of a single Mn phase,by electrochemical dealloying prepared nanoporous Ni-Co alloy,formed the "ring" skeleton structure,its size is about 50~100 nm,aperture is about dozens to hundreds of nanometer s.The analysis of nanoporous Ni-Co alloy hydrogen performance,found that under the current density of 0.15 A·cm-2,The hydrogen evolution overpotential of nanoporous Ni-Co alloy is 192 m V,and at 0.1 A·cm-2 current density,the alloy electrode exhibits good electrochemical stability over a long period of continuous electrolysis.By comparison with the same ratio of Ni-Fe and Ni-Cu alloy were prepared by the same preparation process and experimental conditions,the nanoporous Ni-Fe alloy prepared by dealloying Ni20Fe10Mn70 showed the optimum hydrogen evolution performance.