Linear sweep voltammetry of Pb²⁺/Pb⁰ in oxide melts model and simulation of electrode process

Voltammograms with a bending point were found in the linear sweep voltammetry (LSV) of Pb²⁺/Pb⁰ redox systems in high temperature oxide melts. A model for the voltammogram was constructed in terms of a reversible redox reaction forming an insoluble deposit. The model involves a reaction of the deposit with an electrode metal, producing a metal solid solution and a liquid alloy. The whole shape of the voltammogram was reproduced by means of a computer simulation in terms of the model in which the diffusion process was solved using a difference equation of Fick's second law with appropriate boundary conditions. The present analysis of Mⁿ⁺/M⁰ systems using the bending point will allow the extension of the LSV method to a wider variety of systems and be valuable for thermodynamic studies in high temperature melts.