Electrochemical behavior of cerium ion in molten LiCl-KCl

The electrode process of cerium(III) on the Mo electrode in eutectic LiCl-KCl melt was investigated by electrochemical transient techniques in the temperature range of 673–783 K, respectively. These results unanimously indicated that the reduction process of cerium(III) to cerium metal was a single step exchanging three electrons which was controlled by diffusion of cerium(III). Diffusion coefficients (DCe(III)) in eutectic LiCl-KCl melt were determined by cyclic voltammetry, chronopotentiometry and square wave voltammetry. An empirical diffusion coefficient function depending on temperature was proposed: lnDCe(III)=−2.129−5704/T. The formal potentials (Eθ′Ce(III)/Ce(0) versus Ag/AgCl reference electrode) at different temperatures were obtained from chronopotentiometry, which were –2.10 V (673 K) and –2.07 V (733 K), respectively.