Temperature dependence of¹⁹F NMR and ion transport parameters of fluoride ion conductors SnF₂—PbF₂and 2SnF₂—NH₄F prepared by mechanical milling

Abstract

Abstract19F NMR studies have been carried out on mixed metal fluorides composed of SnF2—PbF2 and 2SnF2—NH4F and prepared by mechanical milling. Motional narrowing observed in the variation of 19F NMR linewidth as a function of temperature for both the systems suggests the occurrence of F− ion diffusion. The variation of different ion transport parameters calculated from NMR results like jump frequency, diffusion coefficient, and conductivity with temperature has been found to be closely related with experimentally measured conductivity results.

Correlation Between Ion Diffusional Motion and Ionic Conductivity for Different Electrolytes Based on Ionic Liquid

“…Thus the correlation discussed in Figure is between the line narrowing observed in the line width of 1 H and 19 F NMR peaks and the total ionic conductivity of these electrolytes at different temperatures. The above results are also consistent with earlier NMR results reported for mixed fluoride ion conductors SnF 2 −PbF 2 and 2SnF 2 −NH 4 F prepared by mechanical milling . Motional narrowing observed in the variation of 19 F NMR line width with temperature has been reported to be closely correlated with experimentally measured ionic conductivity and other ion transport parameters calculated from NMR data.…”

“…The above results are also consistent with earlier NMR results reported for mixed fluoride ion conductors SnF 2 -PbF 2 and 2SnF 2 -NH 4 F prepared by mechanical milling. 41 Motional narrowing observed in the variation of 19 F NMR line width with temperature has been reported to be closely correlated with experimentally measured ionic conductivity and other ion transport parameters calculated from NMR data.…”

Nanocrystalline CaF2 particles obtained by high-energy ball milling

“…The products were investigated exclusively by X-ray diffraction (XRD) [13]. Further studies were published on milling of PbF 2 and NH 4 F with SnF 2 to examine the influence of grain sizes on the ion conductivity [14][15][16]. More recently, mechanochemical reactions of alkali acid bifluorides (MHF 2 ) with alkali halides (MX) were studied by XRD and IR spectroscopy [17].…”

Mechanochemistry of fluoride solids: from mechanical activation to mechanically stimulated synthesis

“…This high conductivity can be in addition considerably increased by the mechanochemical synthesis. Structural disorder in the grain surfaces, small particle sizes, introduced defects and short diffusion paths are responsible for this additional effect [25][26][27][28]. For example, the high electric conductivity of PbSnF 4 is shown in Fig.…”