NaCl-KCl-SmCl_(3)熔盐体系中Sm^(3+)在W电极上的电化学行为

Electrochemical Behavior of Sm^(3+)on W Electrode in NaCl-KCl-SmCl_(3) Molten Salt System

在温度750℃,使用三电极,以NaCl-KCl作为电解质,SmCl_(3)作为材料,运用循环伏安法、方波伏安法和计时电流法研究了Sm^(3+)在NaCl-KCl-SmCl_(3)体系中的电化学行为。结果表明:Sm^(3+)在W电极上的电化学还原是得到1个电子的过程,其电子转移表达式为:Sm^(3+)+e-=Sm2+,反应是准可逆反应,且没有发现其他电子转移行为;Sm^(3+)在W电极上的电化学还原是以扩散为控制步骤,且Sm^(3+)在NaCl-KCl-SmCl_(3)熔盐体系中的扩散系数为D=4.045±0.005×10^(-5) cm^(2)/s。

The electrochemical behavior of Sm^(3+)was studied via electrochemical method.It is of practical significance to prepare Sm alloy by molten salt electrolysis.Three electrode electrolysis system was used at 750℃with NaCl-KCl as electrolyte and SmCl_(3) as raw materials for electrolysis.The electrochemical behavior of Sm^(3+)in NaCl-KCl-SmCl_(3) system was studied by cyclic voltammetry,square wave voltammetry and chronoamperometry,respectively.The results show that the reduction of Sm^(3+)on W electrode is a process to obtain one electron,and the expression of electron transfer is SmCl_(3)++e-=Sm2+.The reaction is quasi reversible,no other electron transfer behavior was found.The electrochemical reduction of Sm^(3+)on W electrode is controlled by diffusion,the diffusion coefficient in NaCl-KCl-SmCl_(3) molten salt system is D=4.045±0.005×10^(-5) cm^(2)/s.