Sotomayor Lozano, María EugeniaLevenfeld Laredo, BelénVarez, AlejandroSanz, Jesús2020-10-212020-10-212017-10-05Journal of alloys and compounds, 720, Oct. 2017, Pp. 460-4650925-83881873-4669 (online)https://hdl.handle.net/10016/31262The synthesis by solid state reaction of new fast ion conductors with perovskite structure was carried out. The crystal structure and electric properties of the La1/2+1/2xLi1/2-1/2xTi1-xAlxO3 (0 ≤ x ≤ 1) solid solution were investigated by powder X-ray diffraction and impedance spectroscopy. All compositions of the La1/2Li1/2TiO3-LaAlO3 system, exhibited a single cubic perovskite structure (ac approximate to 3.87-3.79 angstrom; SG Pm-3m). The progressive decrease in the unit cell parameters agrees with the lower ionic radii of Al3+ in relation to Ti4+, which are allocated in the same octahedra. An upward deviation from the lineal ideal solid solution behavior described by Vegard's law was observed and it was tentatively associated with a volume excess created by solid dilution of non-isovalent cations. Structural features were deduced from Rietveld analysis of XRD patterns. Ti(Al)O6 octahedra are regular and La/vacancies are randomly distributed in A-site of the perovskite. The conductivity decreased almost four orders of magnitude with the Li content. This important decrease on the conductivity was attributed to the charge carrier (Li+) decrease and the blockade of the perovskite conduction pathways by La ions, according to a three dimensional percolative process. In consequence we present here a new example of percolative system of ionic conductors and the results confirm the important role played by effective vacant A-sites, neff = [Li] + nA, on Li conductivity of this fast ion conductors family with perovskite structure.6eng© 2017 Elsevier B.V. All rights reserved.This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Atribución-NoComercial-SinDerivadas 3.0 EspañaX-Ray diffractionIonic conductionSolid-state electrolyteLi-batteriesPercolative phenomenaresearch articleMaterialeshttps://doi.org/10.1016/j.jallcom.2017.05.278open access460465JOURNAL OF ALLOYS AND COMPOUNDS720AR/0000020247