Preparation Of Magnesium Nickel And Zinc Nickel Alloy By Electrodeposition Of Ionic Liquids

As an important strategic material,nickel alloy have crucial significance in the field of hydrogen storage and corrosion resistance.Electrodeposition is one of the most important methods for the preparation of nickel alloys.The traditional plating of nickel alloysare mainly carried out in the aqueous solution containing inorganic salts,but it has the disadvantages of complex process,high cost and so on.As a new kind of green solvent,ionic liquidanalogues are an excellent electrolyte for electrodeposition of nickel alloys because of its excellent properties such as wide electrochemical window,wide liquid temperature range and no hydrogen evolution reaction.This paper uses low cost and simple synthesisbenzyl triethyl ammonium chloride-glycerol-nickel chloride-magnesium chloride?TEBAC-GL-NiCl₂-MgCl₂?and choline chloride urea-ethylene glycol-nickel oxide-zinc oxide?ChCl-urea-EG-Ni₂O₃-ZnO?as electrolyte,studies on electrodeposition of Mg-Ni alloy and Zn-Ni alloy.The magnesium nickel alloy coating with uniform particle size and uniform thickness was successfully prepared by using TEBAC-GL-NiCl₂-MgCl₂ ionic liquidanalogues as electrolyte and copper as cathode and graphite as anode.By cyclic voltammetry,chronoamperometry and other electrochemical methods,we systematically studied the electrodeposition behavior of Ni alloy and Mg-Ni alloy in the system.And composition and morphology of the coating were analyzed by means of XRF,XRD and SEM.The experimental result indicated thatthe conductivity of ionic liquid increase significantly along with the rise of temperature;the addition of Mg²⁺ in TEBAC-GL-NiCl₂ ionic liquidanalogues,the reduction current of the CV curve increased significantly,could realize the Mg-Ni alloy co-deposition;when the concentration of Mg²⁺ was 0.005mol·L^-1,the concentration of Ni²⁺ was 0.1 mol·L^-1,the difference between the equilibrium potential of Mg and Ni is the smallest,and is 1.2532V in Tafel curves;the electrodeposition of Ni and Mg-Ni alloys is a three-dimensional instantaneous nucleation/growth model in ionic liquid analogues when the glassy carbon electrode is used as the working electrode;when the cell voltage was 2.3 V,temperature was 253K,and the concentration of Mg²⁺,the concentration of Ni²⁺ were 0.1 mol·L^-1,the content of magnesium in the deposit was the highest,and the mass fraction was 12.13%.The zinic nickel alloy coating with uniform particle size and uniform thickness was potentiostatic electrodeposited by using ChCl-urea-EG-Ni₂O₃-ZnO ionic liquidanalogues as electrolyte in three electrode system of electroless copper plating iron sheet as working electrode,platinum electrode as the counter electrode and high purity silver as the reference electrode.By cyclic voltammetry,Tafel curve test and other electrochemical methods,we systematically studied the electrodeposition behavior of Ni alloy and Mg-Ni alloy in the system.And composition and morphology of the coating were analyzed by means of XRF,XRD and SEM.The experimental result indicated thatthe addition of Ni???leads to positive shift of initial reduction potential of ChCl-urea-EG-ZnO system.And the positive shift of Zn oxidation peak occurred in the process of positive scanning,Therefore,the Zn-Ni alloys are formed;the Zn-15wt%Ni alloy deposits with the best corrosion resistance can be obtained when the temperature is 353K,Ni₂O₃ is 5g/L,ZnO is 2g/L and the potential is-1.3V;the ZnO.85Nio.15 alloy deposited in-1.3V have the best corrosion resistance owing to the smallest corrosion current of 0.4?A/cm2and the corrosion potential of-934mV;the Zn0.85Ni0.15 alloy coating appear as the maximum diameter of the semicircle capacitive arc at high frequency of Nyquist,and the Zn0.85Ni0.15 alloy coating has the highest polarization resistance because of its the maximum R_ct.