Low-Temperature Synthesis, Structural and Transport Properties of Doped LAMOX – Electrolytes for IT SOFS

Abstract

Doped La2-xRxMo2-yWyO9 (R= Bi, Gd, Pr, Sm, Nd; x=0-0.5, y=0.5-1) were synthesized via polymerized precursors method or high power mechanical milling (MM). The study of doped LAMOX genesis and structural properties using thermal analysis, XRD, SEM, IR and Raman spectroscopy has revealed that for all cations but Bi substituting La-position, the pure cubic β-phase is formed from polymerized precursors after calcination at 700°C. W-doped LAMOX have been obtained via low temperature calcination of MM products depending on W concentration. Due to a high dispersion of powders, high density pellets of doped LAMOX ceramics have been already obtained after annealing at 950°C. Their electrical conductivity measured by impedance spectroscopy depends on the doping cation nature being sufficiently high (up to 5.6∙10-3 S/cm at 630 ºC) at temperature below 650°C.