A novel approach for substantially improving the sinterability of BaZr_0.4Ce_0.4Y_0.2O_3?¦Ä electrolyte for fuel cells by impregnating the green membrane with zinc nitrate as a sin

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• 作者：Yu Liu ; Youmin Guo ; Ran Ran ; Zongping Shao ; ^{shaozp@njut.edu.cn}
• 关键词：Solid oxide fuel cells ; Proton conductor ; Sintering aid ; Impregnation ; Zinc nitrate
• 刊名：Journal of Membrane Science
• 出版年：2013
• 出版时间：15 June, 2013
• 年：2013
• 卷：437
• 期：Complete
• 页码：189-195
• 全文大小：1437 K

文摘

BaZr_0.4Ce_0.4Y_0.2O_3?¦Ä (BZCY4) has been widely considered to be a promising electrolyte material for H⁺-SOFC, but it is restricted to commercial applications due to its poor densification behavior. A dense BZCY4 pellet was obtained by sintering at 1250 ¡ãC after impregnating the material with a zinc nitrate solution. The dilatometer curves and scanning electron microscopy (SEM) images indicated that the sinterability of the BZCY4 material is effectively improved by impregnating the green membrane with 4 wt % Zn. Moreover, EDX mapping indicated that the Ba, Zr and Ce elements were homogeneously distributed in the BZCY4+4 wt % Zn sample sintered at 1250 ¡ãC. In addition, an integrated SOFC employing a BZCY4+4 wt % Zn electrolyte was successfully fabricated without any cracks and delamination by impregnating the BZCY4 electrolyte membrane with zinc nitrate as a sintering aid. This single cell with a 25 mm thick BZCY4+4 wt % Zn electrolyte membrane exhibited power densities as high as 360 and 276 mW cm^?2 at 700 and 600 ¡ãC, respectively. Electrical conductivity measurements demonstrated that the total conductivities of BZCY4+4 wt % Zn were 0.46¡Á10^?2 S cm^?1, 0.56¡Á10^?2 S cm^?1, 0.20¡Á10^?2 S cm^?1 and 0.40¡Á10^?2 S cm^?1 at 600 ¡ãC in air, wet air, 10 % H₂-Ar and wet 10 % H₂-Ar, respectively.