摘要
研究了LiF-CaF_2-NdF_3熔盐体系中Nd(Ⅲ)的电化学行为,通过循环伏安法和开路计时电位法研究得出Nd(Ⅲ)的还原反应为两步电子转移过程,在惰性W电极上,两步反应的平衡电位分别为-1.58 V及-1.27 V(vs. Pt)。在活性Fe电极上对Nd(Ⅲ)的电化学行为研究发现,Nd与Fe会在-0.72 V和-1.15 V(vs. Pt)形成两种Nd-Fe合金。采用自耗阴极法制备了液态Nd-Fe合金,通过XRD分析Nd-Fe合金主要是由Nd、Fe_(17)Nd_2和Fe_(17)Nd_5组成。
The electrochemical behavior of neodymium in LiF-CaF_2-NdF_3 molten salt was studied in this paper. A two-step electron transfer process was found for the reduction reaction of Nd(Ⅲ) by cyclic voltammetry and open circuit potential. The equilibrium potentials of two reactions for Nd-2 e→Nd~(2+) and Nd~(2+)-e→Nd~(3+) were obtained to be-1.58 V and-1.27 V(versus Pt) on an inert W electrode, respectively. In addition, neodymium was deposited on an iron electrode forming Fe_(17)Nd_2 and Fe_(17)Nd_5 alloys at-0.72 V and-1.15 V(versus Pt), respectively. The liquid Nd-Fe alloy, which was composed of Nd, Fe_(17)Nd_2 and Fe_(17)Nd_5, was prepared by the consumption of iron cathode.
引文
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