Phase transformation and oxygen equilibration kinetics of pure and Zr-doped Ba0.5Sr0.5Co0.8Fe0.2O3−δ perovskite oxide probed by electrical conductivity relaxation
Phase transformation and oxygen equilibration kinetics of pure and Zr-doped Ba0.5Sr0.5Co0.8Fe0.2O3−δ perovskite oxide probed by electrical conductivity relaxation
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通过电导率弛豫探测纯和 Zr 掺杂 Ba0.5Sr0.5Co0.8Fe0.2O3−δ 钙钛矿氧化物的相变和氧平衡动力学
DOI：
10.1063/1.3455908
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发表时间：
2010
影响因子：
4
通讯作者：
H. Bouwmeester
中科院分区：
文献类型：
--
作者：
S. Yakovlev;C. Yoo;Shumin Fang;H. Bouwmeester
电导率弛豫用于监测钙钛矿型氧化物 Ba0.5Sr0.5Co0.8Fe0.2O3−δ 中立方相到六方相变。在 1173 K（立方晶型在该温度下稳定）的原位退火后，在 1073 K 的长期退火过程中进行了电导率弛豫实验。发现由于相变缓慢，表面交换系数和化学扩散系数随时间的减小是相关的。结果表明，B位掺杂Zr的量低至3mol %，可以稳定Ba0.5Sr0.5Co0.8Fe0.2O3−δ的高温钙钛矿立方相，并保持其高氧传输和交换性能。
Electrical conductivity relaxation is used for monitoring the cubic-to-hexagonal phase transition in the perovskite-type oxide Ba0.5Sr0.5Co0.8Fe0.2O3−δ. After in situ annealing at 1173 K, at which temperature the cubic polymorph is stable, electrical conductivity relaxation experiments are conducted during long-term annealing at 1073 K. The decreases in the surface exchange and chemical diffusion coefficients with time due to the sluggish phase transition are found to be correlated. It is demonstrated that B-site doping with Zr to an amount as low as 3 mol % stabilizes the high-temperature perovskite cubic phase of Ba0.5Sr0.5Co0.8Fe0.2O3−δ, with preservation of its high oxygen transport and exchange properties.