Electrochemical study of niobium fluoride and oxyfluoride complexes in molten LiF–KF–K2NbF7 bath

Autor: V Daněk, V Van, J Hı́veš, A Silný
Jazyk: angličtina
Rok vydání: 1999
Předmět:
Zdroj: Electrochemistry Communications, Vol 1, Iss 7, Pp 295-300 (1999)
ISSN: 1388-2481
Popis: The reduction of niobium in an equimolar molten mixture of LiF and KF has been investigated using a cyclic voltammetric technique. A two-step mechanism of reduction of niobium in LiF–KF melt is proposed. The influence of oxide ions on the reduction has been studied and it was found to strongly influence the redox properties and structure of niobium ions in the melt. The presence of oxide ions caused the formation of the mono-oxyfluoride complex [Nb(V)OF5]2−. The formation of the mono-oxyfluoride complex was not complete at 720°C. Free oxide ions caused an appearance of di-oxyfluoride complex. In the redundant oxide ions the di-oxyfluoride complex was converted to [Nb(IV)O2F]− by a redox reaction. Keywords: Niobium, Molten fluorides, Electrodeposition, Cyclic voltammetry, Reduction mechanism
Databáze: OpenAIRE