Electrochemical behaviour of silver and rhenium electrodes in molten alkali fluorides

摘要

Electrochemical oxidation of silver and rhenium electrodes in molten LiF–NaF–KF eutectic at 600 °C was investigated by cyclic and convolutional voltammetry. Simulated Cyclic voltammograms were calculated to reinforce understanding of the reaction mechanism. A theoretical relationship was proposed to determine standard potentials from voltammograms of metallic electrodes having an oxidation process governed by Butler–Volmer kinetics. The reversibility of silver oxidation was established and the number of exchanged electrons and the standard potential of the Ag/Ag(I) couple were determined. The rhenium electrode oxidation process was shown to be quasi-reversible and the Re/Re(x) standard potential was estimated.