Electrodeposition of Zr on graphite in molten fluorides

The electrochemical behavior of Zr(4+) using graphite working electrode has been studied in fused LiF-NaF-ZrF(4) eutectic mixture (temperature range 923-1123 K). In addition to the electrochemical profile related to the deposition/dissolution of Zr metal, the cyclic voltammograms exhibit well-defined peaks attributed to the formation of zirconium carbide. A third contribution relative to the formation of Li-graphite intercalation compound and/or lithium carbide was also proposed for a better interpretation of the voltammogram. Depending on the experimental deposition conditions, the analysis of the deposits by SEM/EDX has revealed the presence of a Zr metal thin film with various porosities and compositions. Moreover, the electrochemical reduction of Zr(IV) in molten fluorides using a graphite electrode allows the extraction of pure Zr metal. (C) 2011 Elsevier B.V. All rights reserved.