Synthesis, structure and electrical properties of Li+-doped pyrochlore Gd2Zr2O7

Irina A. Anokhina, Irina E. Animitsa, Anastasia F. Buzina, Vladimir I. Voronin, Vladimir B. Vykhodets, Tatyana E. Kurennykh, Yuri P. Zaikov

Abstract


The pyrochlore Gd1.55Li0.45Zr2O6.55 was prepared by the solution and solid-state methods. The introduction of lithium in the Gd-sublattice led to decrease in the lattice parameter a = 10.4830(8) Å in comparison with Gd2Zr2O7 (a =10.5346(2) Å). Monitoring of the lithium content in the sample during heat treatments showed a loss of lithium at temperatures above 1100 °C, so, to maintain the stoichiometry of lithium the low temperature sintering methods are required. The sample Gd1.55Li0.45Zr2O6.55 exhibited a predominant oxygen-ion transport over a wide range of temperatures.  Although doping did not lead to an increase in the oxygen-ion conductivity compared to Gd2Zr2O7, it caused the suppression of the hole conductivity.

Keywords


gadolinium zirconate Gd2Zr2O7, pyrochlore, Li+-doping, conductivity

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References


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DOI: https://doi.org/10.15826/chimtech.2020.7.2.02

Copyright (c) 2020 Irina A. Anokhina, Irina E. Animitsa, Anastasia F. Buzina, Vladimir I. Voronin, Vladimir B. Vykhodets, Tatyana E. Kurennykh, Yuri P. Zaikov

© Chimica Techno Acta, 2014-2020
ISSN 2411-1414 (Online), ISSN 2409-5613 (Print)

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