The Research Of Magnesium Electrodeposition Behavior In Grignard Reagent Solution

Magnesium is a promising high energy density battery anode material, so it is of great significance to research the electrodeposition of metal magnesium in organic solution systems for the development of new efficient primary and secondary magnesium batterys.In this paper, firstly, three commercially available Grignard reagent electrolyte magnesium bromide / tetrahydrofuran solution (EtMgBr / THF), ethyl magnesium chloride / tetrahydrofuran solution (EtMgCl / THF) and phenyl magnesium chloride / tetrahydrofuran solution (PhMgCl / THF) was used to compare the electrodeposition behavior of magnesium on three differet cathode materials(planar pure copper substrate, planar plated-copper nickel substrate and foamed plated-copper nickel substrate).It is found that, on the planar substrate, uniform and compact magnesium coating can be get; but inside the planar substrate, the magnesium deposition is very few. It reveals that the deepening plating ability of these three Grignard reagent solutions is low.Secondly, rectangular cathode method was used to study the impact of supporting electrolyte tetrabutylammonium chloride (NBu₄Cl) to the deepening plating ability of Grignard reagent electrolyte EtMgBr / THF. It is found that the area and the component of magnesium electrodeposition on the L-shaped copper electrode surface increased with the concentration of the NBu₄Cl.The best concentration of NBu₄Cl was 0.6M. Then 0.6M NBu₄Cl was added to the EtMgBr / THF solution and the magnesium electrodeposition experiment was done on the formed substrate. The result shows that after the magnesium electrodeposition, the magnesium coating covered outside and inside the foamed substrate, and the component of the magnesium is increased to 60% inside the foamed substrate. It reveals that the deepening plating ability of EtMgBr / THF can be improved by adding NBu₄Cl supporting electrolyte to the solution.Finally, Rectangular cathode method was used to study the impact of pulse electrodeposition method to the deepening plating ability of Grignard reagent electrolyte EtMgBr / THF, and the best pulse electrodeposition parameters were optimized. Then the magnesium electrodeposition experiment was done on the formed substrate. The result shows that, under 0.0500 A/cm² average current density, 80% dutyfactor, 5Hz pulse frequency pulse electrodeposition conditions, the magnesium coating covered outside and inside the foamed substrate, and the component of the magnesium is increased to 60% inside the foamed substrate. It reveals that the deepening plating ability of EtMgBr / THF can be improved by pulsed electrodeposition method.