Improved stability and defect structure of yttrium doped cobaltite PrBaCo2O6–δ

• The structure features and defect equilibria are studied.
• The yttrium doping results in considerable increase of thermodynamic stability.
• The doping is shown to enhance total conductivity at moderate temperatures.

The experimental data for equilibrium oxygen content in double perovskite cobaltite Pr0.9Y0.1BaCo2O6–δ show that the incorporation of yttrium in place of praseodymium results in stabilization of the tetragonal structure in wide limits of oxygen pressure and temperature. The thermodynamic model calculations of defect formation reactions demonstrate that the doping is accompanied with enhanced electron and oxygen ion disordering. The observed properties combination is promising for the using of the yttrium modified cobaltite as a cathode in intermediate temperature SOFCs and a ceramic material for oxygen separation and storage.

The pressure dependent changes of equilibrium oxygen content in Pr0.9Y0.1BaCo2O6–δ at different temperatures.Figure optionsDownload as PowerPoint slide