Concentration of Ce3+ and oxygen vacancies in cerium oxide nanoparticles

被引:372
作者
Dutta, P.
Pal, S.
Seehra, M. S. [1 ]
Shi, Y.
Eyring, E. M.
Ernst, R. D.
机构
[1] W Virginia Univ, Dept Phys, Morgantown, WV 26506 USA
[2] Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA
关键词
D O I
10.1021/cm061580n
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
Temperature variations of the electron magnetic resonance (EMR) spectra and magnetization measurements are used to show that Ce3+ ions in concentration similar or equal to 18% are present in 3 nm CeO2 nanoparticles supported on silica aerogel. It is argued that the presence of Ce3+ implies the defect structure CeO2-x for ceria nanoparticles due to oxygen vacancies. This transformation of Ce4+ to Ce3+ driven by oxygen vacancies may be the key to understanding the catalytic properties of ceria.
引用
收藏
页码:5144 / 5146
页数:3
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