Synthesis and characterization of novel Ge doped Sr 1-y Ca y FeO 3-d SOFC cathode materials
Synthesis and characterization of novel Ge doped Sr 1-y Ca y FeO 3-d SOFC cathode materials
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新型Ge掺杂Sr 1-y Ca y FeO 3-d SOFC正极材料的合成与表征
DOI：
10.1016/j.materresbull.2015.02.014
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发表时间：
2015
影响因子：
5.4
通讯作者：
Porras-Vazquez J
中科院分区：
文献类型：
--
作者：
Porras-Vazquez J
在本文中，我们报告了成功地将锗掺入到Sr 1 − yCayFeO 3 −δ钙钛矿材料中，作为固体氧化物燃料电池的电极材料。据观察，Ge掺杂导致从四元晶胞（具有部分有序的氧空位）到立方晶胞（具有无序的氧空位）的变化。在5%H2/95%N2（高达800 °C）中的退火实验也表明，在还原条件下，15 mol% Ge掺杂的SrFeO 3 −δ样品的立方晶型稳定，与未掺杂的系统相反，未掺杂的系统显示出向氧空位有序的褐锰矿型相的转变。为了研究这些系统作为SOFC阴极的潜力，在空气中研究了在致密Ce0.9Gd0.1O1.95颗粒上包含50%Ce0.9Gd0.1O1.95和50%Sr1 −yCay（Fe/Ge）O3−δ的复合电极。结果表明，与未掺杂样品相比，Ge掺杂样品的面积比电阻（ASR）值有所改善，其中Ge掺杂SrFeO 3 −δ系统的性能最好（SrFe0.85Ge0.15O3−δ在700和800 °C下分别为0.24和0.06 Ω cm 2）。因此，结果表明，锗可以掺入Sr 1-yCayFeO 3-δ基材料中，从而产生具有用作固体氧化物燃料电池（SOFC）阴极材料潜力的材料。
In this paper we report the successful incorporation of germanium into Sr1−yCayFeO3−δperovskite materials for potential applications as electrode materials for solid oxide fuel cells. It was observed that Ge doping leads to a change from a tetragonal cell (with partial ordering of oxygen vacancies) to a cubic one (with the oxygen vacancies disordered). Annealing experiments in 5%H2/95%N2(up to 800 °C) also showed the stabilization of the cubic form in reducing conditions for the 15 mol% Ge-doped SrFeO3−δsample, in contrast to the undoped systems which showed a transition to an oxygen vacancy ordered brownmillerite-type phase. In order to examine the potential of these systems as SOFC cathodes, composite electrodes comprising 50% Ce0.9Gd0.1O1.95and 50% Sr1−yCay(Fe/Ge)O3−δon dense Ce0.9Gd0.1O1.95pellets were examined in air. The results showed an improvement in the area specific resistances (ASR) values for the Ge-doped samples with respect to the undoped ones, with the best performance for the Ge doped SrFeO3−δsystem (0.24 and 0.06 Ω cm2at 700 and 800 °C, respectively, for SrFe0.85Ge0.15O3−δ). Thus, the results show that germanium can be incorporated into Sr1−yCayFeO3−δ-based materials leading to materials with potential for use as cathode materials in solid oxide fuel cells (SOFC).