Properties of A-site nonstoichiometry (Pr_0.4)_xSr_0.6Co_0.2Fe_0.7Nb_0.1O_{3鈭?span style='font-style: italic'>蟽} (0.9聽鈮ぢ?span style='font-style: italic'>x聽鈮ぢ?.1) as symmetrical electrode material for solid oxide fuel cells

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• 作者：Peng Zhang ; Guoqing Guan ; Deni S. Khaerudini ; Xiaogang Hao ; Minfang Han ; Yutaka Kasai ; Kazuhiko Sasagawa ; Abuliti Abudula
• 关键词：Solid-oxide fuel cells ; PxSCFN ; A-site deficiency ; A-site excess ; Symmetrical electrode
• 刊名：Journal of Power Sources
• 出版年：15 February, 2014
• 年：2014
• 卷：248
• 期：Complete
• 页码：163-171
• 全文大小：2423 K

文摘

In order to solve the carbon deposition and sulfur adsorption problems during operations of solid-oxide fuel cells (SOFCs), (Pr_0.4)_xSr_0.6Co_0.2Fe_0.7Nb_0.1O_3鈭?em>蟽 (P_xSCFN, x聽=聽0.9, 0.95, 1.0, 1.05 and 1.1) oxides are synthesized by the solid state reaction method and investigated as both cathode and anode for SOFCs. For P_xSCFN (x聽=聽0.9-1.05) powders, it is found that cubic perovskite phase is formed after sintering at 1050聽掳C; however, when x increases to 1.1, a single impurity phase is detected for P_1.1SCFN sample by X-ray diffraction. The effects of A-site nonstoichiometry on thermal expansion coefficient, electrical conductivity and polarization resistance are investigated. The excess of A-site Pr elements in P_xSCFN (x聽=聽1.05 and 1.1) results in a decrease in grain size and the creation of more active sites for oxygen reduction reaction. AC impedance reveals that P_1.05SCFN as symmetrical electrodes has the best electrochemical catalytic performance both in O₂ and in wet H₂ atmosphere. The maximum power densities of a P_1.05SCFN/LSGM/P_1.05SCFN cell reach as high as 1.13聽W聽cm^鈭? in wet H₂ and 0.67聽W聽cm^鈭? in wet CH₄ at 900聽掳C. Therefore, P_1.05SCFN is a potential symmetrical electrode material for SOFCs.