X-RAY ABSORPTION STUDIES OF CERIA WITH TRIVALENT DOPANTS

被引：78

作者：

LI, P ^{[1
]}

CHEN, IW ^{[1
]}

PENNERHAHN, JE ^{[1
]}

TIEN, TY ^{[1
]}

机构：

[1] UNIV MICHIGAN,DEPT CHEM,ANN ARBOR,MI 48109

来源：

JOURNAL OF THE AMERICAN CERAMIC SOCIETY | 1991年 / 74卷 / 05期

关键词：

X-RAY; ABSORPTION; CERIA; DOPANTS; DEFECTS;

D O I：

10.1111/j.1151-2916.1991.tb04328.x

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

The local structural environments of Sc3+ and Gd3+ in ceria were studied for the first time by using EXAFS (extended X-ray absorption fine structure) and XANES (X-ray absorption near edge structure) spectroscopy. Our results indicate that Sc3+ in 10-mol%-Sc2O3-doped ceria has a 7-fold-coordinated Sc-ordered structure with two different Sc-O distances (2.13 and 2.26 angstrom). An octahedrally coordinated Sc-O cluster is present in 5 mol% Sc2O3-5 mol% Gd2O3-CeO2, because of the strong scavenging effect of Sc3+ ions on oxygen vacancies created by Gd3+. The Gd3+ in this sample is largely unassociated. Sc2O3 (5 mol%) and Gd2O3 (5 or 10 mol%) form random solid solutions with CeO2. These results are consistent with the current concept of defect structures in this structural family.

引用

页码：958 / 967

页数：10

共 25 条

[1] MICRODOMAIN DESCRIPTION OF DEFECTIVE FLUORITE-TYPE PHASES CAXM1-XO2-X(M=ZR,HF - X= 0.1-0.2) [J].