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Achieving fast oxygen diffusion in perovskites by cation ordering

A. A. Taskin·A. N. Lavrov·Yoichi Ando
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Abstract

The oxygen-exchange behavior has been studied in half-doped manganese and cobalt perovskite oxides. We have found that the oxygen diffusivity in Gd_{0.5}Ba_{0.5}MnO_{3-δ} can be enhanced by orders of magnitude by inducing crystallographic ordering among lanthanide and alkali-earth ions in the A-site sublattice. Transformation of a simple cubic perovskite, with randomly occupied A-sites, into a layered crystal GdBaMn_2O_{5+x} (or isostructural GdBaCo_2O_{5+x} for cobalt oxide) with alternating lanthanide and alkali-earth planes reduces the oxygen bonding strength and provides disorder-free channels for ion motion, pointing to an efficient way to design new ionic conductors.

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A. A. Taskin, A. N. Lavrov, Yoichi Ando. 2005-01-07. Achieving fast oxygen diffusion in perovskites by cation ordering. https://doi.org/10.1063/1.1864244

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