Current efficiency of Ga electrodeposition under different anions concentrations

摘要

The gallium electrodeposition from alkaline solution has a very low current efficiency,the reason for which is still not quite understood.The effects of electrode materials used for gallium electrodeposition,as well as the effects of Na OH concentration and the anions concentrations in the solution,including SO_4^(2-),SiO_3^(2-),CO_3^(2-),AlO_2^-,F^-,and Cl^-,on the deposition were analyzed in this study.The suitable materials of SUS316–SUS316 were suggested for the gallium electrodeposition.Based on the electrode couples,the Na OH concentration of 4 mol L^(-1)for gallium electrodeposition exhibits the greatest current efficiency.Moreover,the current efficiency would decrease in the electrolyte along with the increasing concentration of the anions,except that,0.2 mol L^(-1)Cl-in the solution slightly improves the current efficiency of gallium electrodeposition.Moreover,the gallium deposited on the cathode from the solution with 0.6 mol L^(-1)SiO_3^(2-)appears tiny black in color and coarse.Meanwhile,SUS304 is shown to be not suitable to be used as cathode for the gallium electrodeposition from the alkaline solution.