Synthesis, structure and electrical properties of Li + -doped pyrochlore Gd 2 Zr 2 O 7

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

doi:10.15826/chimtech.2020.7.2.02

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 Gd_1.55Li_0.45Zr₂O_6.55was 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 Gd_1.55Li_0.45Zr₂O_6.55 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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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