A Cyclic Voltammetric Study of the Dissolution of Tellurium

Abstract

A cyclic voltammetric study of the oxidation and reduction of elemental tellurium over the pH range 0-14 has been undertaken with tellurium disk electrodes which could be rotated. In both oxidation and reduction, the behaviour of tellurium is largely that expected from the predictions of the E-pH diagram for this element. Exceptions to this general principle were observed during the oxidation of tellurium at both low and high pH where it was found that tellurous acid was relatively quick to form and slow to dissolve; this led to a type of passivation behaviour. On the reduction side, the system behaved in a complex, fashion between pH 8 and 11 with both HTe - and Te₂^2- being formed.