Electrochemical reduction of ytterbium in perchloric media

Abstract

The electrochemical behavior of Yb 3+ in perchloric media was studied by cyclic voltammetry and current reversal chronopotentiometry at several temperatures. The results show that the reversible electrochemical reduction of Yb 3+ is followed by homogeneous reactions. The experimentally determined diffusion coefficients of ytterbic ion are 0.41×10 −5 , 0.48×10 −5 and 0.53×10 −5 cm 2 s −1 at 4.2, 9.2 and 14.7°C, respectively, in 0.5 M NaClO 4 solutions. From these data a value of 16 kJ mol −1 (3830 cal mol −1 ) was obtained for the activation energy for diffusion of ytterbic ion. From the activation energy the diffusion coefficient of ytterbic ion at 25.0°C was estimated. The value of 0.67×10 −5 cm 2 s −1 was obtained. In all the experiments the initial pH was maintained at 4.1.