Electrical Conductivity and Phase Transitions in Ferroelectric Solid Solutions Li_0.17Na_0.83Та_уNb_1-уO₃ (y = 0 – 0.5) in High Pressure

Abstract:

Ferroelectric ceramic solid solutions Li_xNa_1-xTa_yNb_1-yO₃ (х = 0.17; у = 0 – 0.5) with the perovskite structure have been obtained by the thermobaric synthesis method. Particularities of their microstructure, elastic properties, electrical conductivity and permittivity have been researched. It has been established that an increase in the thermobaric synthesis temperature leads to a decrease in the Young’s modulus value. Specific static conductivity values have been determined; charge carrier activation enthalpies Н_а have been calculated. The Curie temperature of the samples has been determined to decrease with an increase in tantalum content. A Ferroelectric ceramic solid solution Li_0.17Na_0.83Ta_0.1Nb_0.9O₃ was shown to undergo four structure phase transitions in the temperature range 300-820 К. A Li_0.17Na_0.83Ta_0.1Nb_0.9O₃ has been shown to be a high temperature superionic. Possible mechanisms of the detected phenomena are discussed.

• Periodical: Solid State Phenomena (Volume 310)
• Pages: 6-13
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.310.6
• Online since: September 2020
• Authors: Vadim V. Efremov*, Mikhail N. Palatnikov, Yuriy V. Radyush, Olga B. Shcherbina
• Keywords: Activation Enthalpy, Curie Temperature, Ferroelectrics, High Pressure, Impedance Spectroscopy, Phase Transition, Sodium Niobate, Solid Solutions, Young's Modulus

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