Author/Authors :
Mineshige، نويسنده , , Atsushi and Mieda، نويسنده , , Hiroyuki and Manabe، نويسنده , , Mitsuaki and Funahashi، نويسنده , , Takahiro and Daiko، نويسنده , , Yusuke and Yazawa، نويسنده , , Tetsuo and Nishi، نويسنده , , Mina and Yamaji، نويسنده , , Katsuhiko and Horita، نويسنده , , Teruhisa and Amezawa، نويسنده , , Koji and Yashiro، نويسنده , , Keiji and Kawada، نويسنده , , Tatsuya and Yoshioka، نويسنده , , Hideki، نويسنده ,
Abstract :
An oxygen-excess-type lanthanum silicate (LSO) solid electrolyte with high chemical stability as well as high ion conductivity was developed by optimizing the chemical composition, La9.333 + x(Si6 − yAly)O26 + 1.5x − 0.5y. It was found that La10(Si5.8Al0.2)O26.9 (x = 0.667, y = 0.2) exhibited the highest conductivity among them, and addition of a small amount of iron was effective for the improvement of its chemical stability. The LSO specimen of x = 0.667 and y = 0.2 with iron addition (0.5 mol%) was chemically stable and had a conductivity of 5.6 × 10− 2 S cm− 1 under air at 1073 K, while its electronic conductivity was less than 2.0 × 10− 4 S cm− 1 at the same temperature. The oxygen tracer diffusion coefficient, DO* of this material was determined as 2.0 × 10− 8 cm2 s− 1 at 1073 K.
Keywords :
apatite , Oxyapatite , Lanthanum silicate , solid electrolyte , Solid oxide fuel cell , Diffusion coefficient
