Synthesis, characterization and ionic conductivity of Sr1.5Sb0.5O3−y (y ∼ 0.25)

We describe the synthesis, structural and microstructural characterization of a strontium antimonate, Sr1.5Sb0.5O3−y (y ∼ 0.25), with a cubic, double-perovskite structure and a large concentration of oxygen vacancies with no apparent long-range order. High resolution electron microscopy indicates, however, that short-range ordering phenomena may occur. Electrical conductivity is independent of oxygen partial pressure (pO2) for pO2 < 10−1.25 atm, typical of ionic transport (σ ∼ 10−4 S cm−1 at 600 °C), whereas the conductivity is dominated by p-type charge carriers at higher pO2.

Graphical abstractA strontium antimoniate showing a cubic, double-perovskite structure and a large amount of oxygen vacancies. An important feature of these materials is their ionic conductivity, close to 10−4 S cm−1 at 600 °C, which seems to be related to a noticeable amount of anionic vacancies (y = 0.25), something giving rise to local ordering phenomena as observed by means of electron diffraction and HREM.Figure optionsDownload full-size imageDownload as PowerPoint slide