Understanding of Electrochemical Reduction of Sm in a LiCl- KCl Molten Salt Solution at 773 K

Abstract

The electrochemical reduction of Sm3+ to Sm2+ in a LiCl-KCl eutectic melt has been investigated using chronoamperometry and cyclic voltammetry (CV). In this work, for the first time, the formal potential and standard rate constant of a Sm3+/Sm2+ redox system have been measured at the same time through a curve fitting analysis for experimental CV curves which were obtained in a wide scan rate range of 0.5 to 10 V/s. The regression analysis results showed an excellent fit to all experimental CV data simultaneously, even though the curve fittings were performed within a wide range of initial transfer coefficient values, formal potentials, and standard rate constants. Finally, a proper formal potential, transfer coefficient, and standard rate constant for the Sm3+/Sm2+ redox reaction were successfully extracted by the simultaneous CV curve fitting method.