磁力搅拌下离子液体AlCl_3/Et_3NHCl恒电流法电沉积铝

Constant current electrodeposition of aluminum from AlCl_3/Et_3NHCl ionic liquid under magnetic stirring

磁力搅拌下,在1.75AlCl3/Et3NHCl离子液体中不锈钢电极片上利用恒电流法电沉积制备金属铝。研究发现,AlCl3/Et3NHCl离子液体的黏度随温度的升高而减小,lnμ与T-1符合线性关系;AlCl3/Et3NHCl离子液体的电导率随温度的升高而增大,符合Arrhenius公式。磁力搅拌下恒电流法电沉积铝实验结果表明,转速低于700 r/min时电流效率和沉积速率随着转速的增大而升高,沉积物表面形貌逐渐平整致密,颗粒细化。温度70℃、电流密度22 mA/cm2、转速700 r/min、电沉积90 min下,沉积铝的表面形貌相对比较平整致密,电流效率达到78%,沉积铝的纯度(质量分数)达到97%。

Aluminum was successfully electrodeposited on stainless steel electrodes from aluminum chloride（AlCl3）/triethylamine hydrochloride（Et3NHCl）ionic liquids by constant current electrolysis under magnetic stirring conditions.The electrical conductivities of ionic liquids increased as the electrolyte temperature increased,agreeing with Arrhenius equation.The viscosities of ionic liquids decreased as the electrolyte temperature increased,with a linear relationship of lnμ and T-1.The constant current deposition experiments showed that when the stirring speed was lower than 700 r/min,current efficiency and deposition rate increased as the speed increased,the surface morphology of the deposits became more smooth and denser,with fine particle sizes and uniform distribution.In addition,the electrodeposits obtained on stainless steel electrodes were dense,continuous,and well adherent,and the current efficiency was 78% at a current density of 22 mA/cm2 for 90 min electrolysis at 70 ℃ under stirring speed of 700 r/min.The purity of aluminum electrodeposits on stainless steel electrodes was about 97%（w/w）.