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Stationary anodic process at platinum in KF-NaF-AlF3-Al2O3 melts

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Abstract

The kinetics of the anodic process at platinum in KF-NaF-AlF3-Al2O3 melts in the temperature range 725–800°C is studied using potentiostatic polarization. Platinum is considered as an indifferent oxygen-evolving electrode, and a two-stage scheme is proposed for the anodic process on it. According to this scheme, primary charge transfer with the formation of adsorbed Oads particles is accompanied by their desorption according to a physical or an electrochemical mechanism. The polarization dependences of the anodic process on platinum are calculated under stationary conditions with allowance for the predominance of different stages of the process and a desorption mechanism. The calculated and experimental stationary anodic polarization dependences are compared.

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Correspondence to A. V. Suzdal’tsev.

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Original Russian Text © V.N. Nekrasov, O.V. Limanovskaya, A.V. Suzdal’tsev, A.P. Khramov, Yu.P. Zaikov, 2014, published in Rasplavy, 2014, No. 4, pp. 70–79.

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Nekrasov, V.N., Limanovskaya, O.V., Suzdal’tsev, A.V. et al. Stationary anodic process at platinum in KF-NaF-AlF3-Al2O3 melts. Russ. Metall. 2014, 664–670 (2014). https://doi.org/10.1134/S0036029514080084

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  • DOI: https://doi.org/10.1134/S0036029514080084

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