Oxygen nonstoichiometry, mixed valency and mixed conduction in (La,Sr)(Co,Fe)O3-δ

被引：20

作者：

Mineshige, Atsushi

Abe, Jiro

Kobune, Masafumi

Uchimoto, Yoshiharu

Yazawa, Tetsuo

机构：

[1] Univ Hyogo, Grad Sch Engn, Dept Chem & Mat Sci, Himeji, Hyogo 6712280, Japan

[2] Kyoto Univ, Grad Sch Human & Environm Studies, Dept Interdisciplinary Environm, Sakyo Ku, Kyoto 6068501, Japan

来源：

SOLID STATE IONICS | 2006年 / 177卷 / 19-25期

关键词：

mixed conductor; nonstoichiometry; X-ray absorption; ELECTRICAL-CONDUCTIVITY; SEEBECK COEFFICIENT; CRYSTAL-STRUCTURE;

D O I：

10.1016/j.ssi.2006.08.016

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Defect chemistry for a mixed conductor, La0.6Sr0.4Co0.2Fe0.8O3-delta was studied. Samples were treated under controlled oxygen partial pressure, P(O-2), conditions at 1273 K [10(-11.1) <= P(O-2)/atm <= 1], and cooled to room temperature. Oxygen nonstoichiometry and valences of transition metal ions for the treated samples were evaluated by iodometry and X-ray absorption spectroscopy, respectively. With decreasing P(O-2), preferential reduction of Co3+ to Co2+ was observed, while iron preserved its higher valence above 3 under conditions studied. A dependency of its electrical conductivity on P(O-2) was discussed along with a change in concentration of oxygen vacancies and mixed valences. (c) 2006 Elsevier B.V. All rights reserved.

引用

页码：1803 / 1806

页数：4

共 9 条

[1] Metal-insulator transition and crystal structure of La1-xSrxCoO3 as functions of Sr-content, temperature, and oxygen partial pressure [J].