Journal of Electroanalytical Chemistry, Vol.633, No.2, 291-296, 2009
The influence of electrode material nature on the mechanism of cathodic reduction of ytterbium (III) ions in fused NaCl-KCl-CsCl eutectic
This work presents the influence of electrode material nature on the mechanism of cathodic reduction of ytterbium (III) ions in fused NaCl-KCl-CsCl eutectic at the temperature range 723-1073 K. Transient electrochemical techniques such as linear sweep, cyclic, semi-integral and square wave voltammetry, and potentiometry at zero current have been used in order to investigate the reduction mechanism of ytterbium ions on inert and active working electrodes, transport parameters and thermodynamics properties of the ytterbium compounds. The influence of the material of working electrode on the mechanism of the cathode process was determined. The results obtained show that the reduction reaction Yb(III) + (e) over bar double left right arrow Yb(II) on W electrode is reversible being controlled by the rate of the mass transfer. The diffusion coefficient of [YbCl(6)](3-) complex ions was calculated at different temperatures and the apparent standard electrode potential of the soluble-soluble redox system Yb(3+)/Yb(2+) was obtained. The reduction reaction of ytterbium (III) ions on Al active electrode was investigated. Al(2)Yb and Al(3)Yb alloys are formed during the polarization on the surface of working electrode. (C) 2009 Elsevier B.V. All rights reserved.