Ion-conducting materials based on Y-doped SrSnO3: Features of ceramics preparation and transport properties

Designing ion-conducting perovskite oxides is of great interest in high-temperature electrochemistry, particularly with regard to the development of novel electrolyte or electrode materials that have the potential for their utilization in solid oxide cells. While state-of-the-art proton-conducting materials based on cerate-zirconates have already been identified, fundamental studies on new promising proton-conducting oxide systems are still important to reveal common or undiscovered relationships between composition, structure, and proton transport features. In this study, we present the data on the preparation of powder and ceramic SrSn1−xYxO3−δ materials and their further characterization by X-ray diffraction (including high-temperature), scanning electron microscopy, dilatometry, and electrical analyses. Within the investigated concentration range (0 ≤ x ≤ 0.2), all materials are found to be single phase with a certain variation of crystal structure symmetry depending on composition and temperature. No detectable dopant exsolution or strontium segregation is found in either the surface or bulk portions of the ceramic samples, but their conductivity shows an atypical behavior, dropping significantly across the Y content (x) boundary of 0.1/0.15. This can be attributed to the microstructural features of the prepared ceramics, consisting of the formation of either conventionally spherical or unusual rectangular (anisotropic) grains. Possible explanations for the observed results are also presented. Therefore, this work highlights the basic properties of Y-doped SrSnO3, including structural, microstructural, thermal, and electrical aspects at high temperatures. To the best of our knowledge, no systematic studies on the SrSn1−xYxO3−δ system have been published in the literature.