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 - yAl y)O26 + 1.5x - 0.5y. It was found that La 10(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.
|ジャーナル||Solid State Ionics|
|出版ステータス||Published - 2014 9月 1|
ASJC Scopus subject areas
- 化学 (全般)