Chronopotentiometry at platinum electrode in KF-NaF-AlF 3 -Al 2 O 3  melt

A. V. Suzdaltsev; A. P. Khramov; Yu. P. Zaikov; O. V. Limanovskaya; V. N. Nekrasov

doi:10.15826/chimtech.2015.2.3.020

Chronopotentiometry at platinum electrode in KF-NaF-AlF₃-Al₂O₃ melt

A. V. Suzdaltsev, A. P. Khramov, Yu. P. Zaikov, O. V. Limanovskaya, V. N. Nekrasov

Abstract

Some features of the mechanism of the anode process on platinum in KF–NaF–AlF₃–Al₂O₃ melt at 750-780 °C depending on the of anodic current density (0.5 mA/cm² to 2.0 A/cm²) and anodic pulse duration have been studied using chronopotentiometry method. In curves of change in the platinum anode potential a small peak at current densities of 10-30 mA/cm² and a clear peak at current densities of 0.5-2.0 A/cm² are recorded when the current is cut on. Analysis of dependencies of the transition time on the current density indicates that the first peak in curve is associated with the formation of an oxide compound on the platinum surface, and the second one is related to hindering the diffusion for delivery of electroactive particles to its surface.

Keywords

oxide-fluoride melts; chronopotentiometry; platinum; oxidation

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References

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DOI: https://doi.org/10.15826/chimtech.2015.2.3.020

Copyright (c) 2015 A. V. Suzdaltsev, A. P. Khramov, Yu. P. Zaikov, O. V. Limanovskaya, V. N. Nekrasov