Contribution à l'étude des propriétés structurales, dynamiques et de conduction des halogénures mixtes de plomb PbCl2xBr2(1-x)

Abstract : Solid electrolytes represent an important class of materials which are currently being explored for use in advanced microelectronics devices. The research described in this thesis has been focused on the ion dynamics of fifteen compisitions in the system PbCl2-PbBr2. These lead halides exhibit complete mutual solid solubility, and crystallise in the same orthorhombic structure, which presents two non equivalent anion sites. The melt growth procedure (Bridgman technique) is new, and yields optically transparent crystals with most often excellent cleavage properties. Xrays scattering experiments reveal preferential site occupancy for Cl and Br, while thermal studies reveal that there is no partial melting of any anion sublattice. A complete assignment of Raman peaks is made by comparison with X-rays studies. All these results confirm that PbClBr is completely ordered, while the maximum of disorder is obtained for x=0.25 and x=0.75, i.e. when one of the anion sublattices is occupied half by each sort of ions (Br, Cl). The electrical properties of the solid solution crystals have been studied thoroughly with advanced impedance spectroscopy techniques in a wide range of frequencies. The bulk data alaong with the cristallographic data have been used to elucidate the defect parameters of the mobile Schottky defects, i.e. migration and formation enthalpies, as a function of composition and crystallographic orientation. A detailed description of the conduction mechanism resulted from an elaborate analysis of the structural and electrical studies
Complete list of metadatas

Cited literature [90 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01775568
Contributor : Administrateur Du Ccsd <>
Submitted on : Tuesday, April 24, 2018 - 3:36:23 PM
Last modification on : Tuesday, July 3, 2018 - 1:22:03 AM
Long-term archiving on : Wednesday, September 19, 2018 - 9:27:50 AM

File

Lumbreras.Martine.SMZ8720.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01775568, version 1

Collections

Citation

Martine Lumbreras. Contribution à l'étude des propriétés structurales, dynamiques et de conduction des halogénures mixtes de plomb PbCl2xBr2(1-x). Autre [cond-mat.other]. Université Paul Verlaine - Metz, 1987. Français. ⟨NNT : 1987METZ020S⟩. ⟨tel-01775568⟩

Share

Metrics

Record views

270

Files downloads

15