High valence transition metal doped strontium ferrites for electrode materials in symmetrical SOFCs
High valence transition metal doped strontium ferrites for electrode materials in symmetrical SOFCs
复制标题
DOI：
10.1016/j.jpowsour.2013.10.118
复制
发表时间：
2014-03-01
影响因子：
9.2
通讯作者：
Losilla, E. R.
中科院分区：
文献类型：
--
作者：
Fernandez-Ropero, A. J.;Porras-Vazquez, J. M.;Losilla, E. R.
在本文中，我们成功地将高价过渡金属，即Cr， Mo， W, v, Nb, Ti， Zr掺入srfeo3 - δ钙钛矿材料中，作为固体氧化物燃料电池对称电极材料的潜在应用。观察到，掺杂导致氧空位由偏有序的正交结构转变为无序的立方结构。这些电极与Ce0.9Gd0.1O1.95 （CGO）和la0.8 sr0.2 ga0.8 mg0.2 -delta （LSGM）电解质的化学相容性至少达到1100℃。在800℃下5% H-2-Ar条件下的热退火实验也显示了掺杂样品在还原条件下的稳定性，表明它们可能适用于阴极和阳极应用。相反，未掺杂的srfeo3 - δ的还原导致观察到额外的峰，表明形成了伴随氧空位有序的褐磨矿结构。在空气和5% H-2-Ar的CGO和LSGM密集电解质球团上测试了这些电极的性能。在两种气氛下，观察到相对于母体化合物，掺杂样品的面积比电阻（ASR）值有所改善。因此，研究结果表明，高价过渡金属可以掺入srfeo3 - δ基材料中，并对电化学性能产生有益的影响，使其有可能适合用作对称SOFC的正极和阳极材料。(C) 2013 Elsevier B.V.版权所有
In this paper we report the successful incorporation of high valence transition metals, i.e. Cr, Mo, W, V. Nb, Ti, Zr into SrFeO3-delta perovskite materials, for potential applications as symmetric electrode materials for Solid Oxide Fuel Cells. It is observed that the doping leads to a change from an orthorhombic structure (with partial ordering of oxygen vacancies) to a cubic one (with the oxygen vacancies disordered). These electrodes are chemically compatibles with Ce0.9Gd0.1O1.95 (CGO) and La0.8Sr0.2Ga0.8Mg0.2O3-delta (LSGM) electrolytes at least up to 1100 degrees C. Thermal annealing experiments in 5% H-2-Ar at 800 degrees C also show the stability of the doped samples in reducing conditions, suggesting that they may be suitable for both cathode and anode applications. In contrast, reduction of undoped SrFeO3-delta leads to the observation of extra peaks indicating the formation of the brownmillerite structure with the associated oxygen vacancy ordering. The performance of these electrodes was examined on dense electrolyte pellets of CGO and LSGM in air and 5% H-2-Ar. In both atmospheres an improvement in the area specific resistances (ASR) values is observed for the doped samples with respect to the parent compound. Thus, the results show that high valence transition metals can be incorporated into SrFeO3-delta-based materials and can have a beneficial effect on the electrochemical performance, making them potentially suitable for use as cathode and anode materials in symmetrical SOFC. (C) 2013 Elsevier B.V. All rights reserved.