Effect of the ionic radius of stabilizing oxide cation on the local structure and transport properties of zirconia based solid solutions

Features of the local structure of ZrO2-Yb2O3, ZrO2-Y2O3-Yb2O3 and ZrO2-Sc2O3-Yb2O3 single crystals have been studied using optical spectroscopy. The probability of oxygen vacancies to occupy the first co-ordination shells of the Sc3+, Yb3+ and Y3+ stabilizing oxide cations has been shown to vary in the test solid solutions. Furthermore it has been shown that the probability of oxygen vacancies to occupy the first co-ordination shells of the Sc3+ ions is higher than their probability to occupy the first coordination shells of the Yb3+ and Y3+ ions. It has been shown that the transport properties of the ZrO2-Sc2O3-Yb2O3 and ZrO2-Y2O3-Yb2O3 solid solutions depend significantly on the ionic radii of the stabilizing oxide cations located in the first coordination shells of oxygen vacancies. For cations with small ionic radii (Sc3+, Yb3+) the height of the barrier which depends on the potential energy of the elastically deformed lattice is lower and the ionic conductivity is therefore higher. (C) 2021 Elsevier B.V. All rights reserved.