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 (D-Ce(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: lnD(Ce(III))=-2.129-5704/T. The formal potentials (E-Ce(III)/Ce(0)(theta') 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.