Ion Mobility in the Fluorite Solid Solutions 50PbF₂–30BiF₃–20K(Na)F According to ¹⁹F, ²³Na NMR Data

V.Ya. Kavun, A.B. Slobodyuk, I.A. Telin, R.M. Yaroshenko, I.G. Maslennikova, V.K. Goncharuk, V.I. Kharchenko

a Institute of Chemistry, Far Eastern Branch of RAS, Vladivostok, Russia.
Far-Eastern Federal University, Vladivostok, Russia.
Institute of Chemistry, Far Eastern Branch of RAS, Vladivostok, Russia.

DOI: 10.4236/ampc.2012.24B020                

Abstract

 Ion mobility in solid solutions of the fluorite structure 50Pb₂–30BiF₃–20KF (I) and 50Pb₂–30BiF₃–20NaF (II) was studied by NMR method. Analysis of ¹⁹F, ²³Na NMR spectra made it possible to reveal the character of ion motions in the fluoride and sodium sublattices with temperature variation, to determine the types and temperature ranges in which they took place. It was found that the dominant form of ionic mobility in the samples I and II above 380 K was the diffusion of fluoride and sodium ions. According to preliminary results of electro-physical studies, the conductivity reached values of ~ 2×10^–2 – 10^–3 S/cm above 500 K. The solid solutions I and II can be recommended as a basis for use in the development of new functional materials.

Keywords

Solid Solutions 50PbF₂–30BiF₃–20K(Na)F; Ion Mobility; Ionic Conductivity; ¹⁹F, ²³Na NMR spectra; functional materials

Conflicts of Interest

The authors declare no conflicts of interest.

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