Representative volume element size for accurate solid oxide fuel cell cathode reconstructions from focused ion beam tomography data
Representative volume element size for accurate solid oxide fuel cell cathode reconstructions from focused ion beam tomography data
复制标题
DOI：
10.1016/j.electacta.2012.04.133
复制
发表时间：
2012-11-01
影响因子：
6.6
通讯作者：
Ivers-Tiffee, Ellen
中科院分区：
文献类型：
--
作者：
Joos, Jochen;Ender, Moses;Ivers-Tiffee, Ellen
固体氧化物燃料电池的电极性能很大程度上受到其微观结构特征的影响。介绍了混合导电La0.58Sr0.4Co0.2Fe0.8O3-δ（LSCF）阴极的三维重建，并对其进行了详细描述。首先，分析了FIB/SEM（聚焦离子束/扫描电子显微镜）断层扫描的多步骤过程，识别了误差源并提出了应对措施。特别强调足够的 SEM 图像分辨率、可靠结果所必需的代表性体积元素以及数值模拟的重要方面。我们的校正重建数据集代表类似于 2800 μ m(3) 的体积，并包含类似于 96 x 10(6) 体素。然后，该数据集用于计算：(i) LSCF 阴极的体积比表面积，(ii) 体积/孔隙率分数，以及 (iii) LSCF 和孔隙在恒定基础面积下的弯曲度，但重构电极的高度不断增加。此外，这些微观结构参数的过程是针对三个代表性体积单元独立计算的。 (C) 2012 Elsevier Ltd. 保留所有权利。
Electrode performance in solid oxide fuel cells is strongly affected by its microstructure characteristics. A three-dimensional reconstruction of a mixed-conducting La0.58Sr0.4Co0.2Fe0.8O3-delta (LSCF)-cathode is introduced, which gives a detailed description thereof. At first, the multistep procedure of FIB/SEM (focused ion beam/scanning electron microscopy) tomography is analyzed, error sources are identified and measures taken against are presented. Special emphasis is turned on adequate SEM image resolution, on representative volume elements essential for trustworthy results and on important aspects of the numerical simulation.Our corrected reconstruction data set represents a volume of similar to 2800 mu m(3) and contains similar to 96 x 10(6) voxels. This data set is then used for calculating: (i) volume-specific surface area of the LSCF cathode, (ii) volume/porosity fraction, and (iii) tortuosity of LSCF and pores at a constant base area, but for an increasing height of the reconstructed electrode. Moreover, the course of these microstructure parameters is calculated independently for three representative volume elements. (C) 2012 Elsevier Ltd. All rights reserved.