Influence of pyrochlore domains on the structure and electrical properties Gd2-xDyxZr1.5Hf0.5O7 energy materials

Electrical properties of the Gd2Zr2O7 ceramics depend on its structural stability. Gd2Zr2O7 can adopt an ordered pyrochlore or a disordered defect fluorite phase depending on the preparation methods and annealing temperature. In the present study, Gd2-xDyxZr1.5Hf0.5O7 nanoceramics are synthesized through combustion method. Oxide ion ordering in the cubic lattice of the prepared materials is studied by X-ray diffraction and Raman spectroscopy. Electron microscopy is used to analyze the particulate properties of the nanoceramics and surface morphology of the dense ceramics. Impedance spectroscopy is used to analyze the ionic transport properties of the bulk ceramics. It is observed that the ionic conductivity of the prepared materials increases with the decrease of pyrochlore domains and reaches a maximum at the order - disorder transformation boundary. The maximum value of ionic conductivity observed in this study is 2.03 x 10(-3) Scm(-1) for Gd2-xDyxZr1.5Hf0.5O7 at 850 degrees C. Decrease of activation energy and ion-ion interactions are the main factors for the improved ionic conduction. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The electrical properties of Gd2Zr2O7 ceramics depend on their structural stability, with different preparation methods and annealing temperatures leading to varying material structures that impact ion conduction. Investigating Gd2-xDyxZr1.5Hf0.5O7 nanoceramics revealed improved ionic conductivity with structural adjustments, reaching a maximum value.