The electrochemical behaviour of terbium at a tungsten electrode, in eutectic LiCl-KCl melts, was investigated at 673 to 823K by means of cyclic voltammetry, chronopotentiometry and chronoamperometry. It was found that during cathodic polarization, the deposition of metallic Tb from the chloride mixture onto the tungsten surface proceeded in a single step, and that electrocrystallization played an important role. Experimental current-time transients obeyed theoretical models based upon instantaneous nucleation, with 3-dimensional growth of the nuclei; regardless of the applied overpotential. From chronopotentiometric measurements, the diffusivity of Tb(III) ions was determined by applying the Sand equation and modifying the immersion depth of the working electrode in stages. The activation energy for diffusion was 33.4kJ/mol. The data could be described by: log[D(cm2/s)] = -2.79 -1744/T.

Electrochemistry of Terbium in the Eutectic LiCl-KCl. M.R.Bermejo, J.Gómez, A.M.Martínez, E.Barrado, Y.Castrillejo: Electrochimica Acta, 2008, 53[16], 5106-12