Raman Analysis of Mode Softening in Nanoparticle CeO2-δ and Au-CeO2-δ during CO Oxidation

被引：400

作者：

Lee, Youjin ^{[1
]}

He, Guanghui ^{[1
]}

Akey, Austin J. ^{[1
]}

Si, Rui ^{[2
]}

Flytzani-Stephanopoulos, Maria ^{[2
]}

Herman, Irving P. ^{[1
]}

机构：

[1] Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA

[2] Tufts Univ, Dept Chem & Biol Engn, Medford, MA 02155 USA

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2011年 / 133卷 / 33期

关键词：

WATER-GAS SHIFT; PROBING DEFECT SITES; CERIUM OXIDE; LATTICE-PARAMETERS; DOPED CERIA; X-RAY; CATALYSTS; CEO2; SPECTROSCOPY; GOLD;

D O I：

10.1021/ja204479j

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Oxygen vacancy levels are monitored during the oxidation of CO by CeO2-delta nanorods and Au-CeO2-delta nanorods, nanocubes, and nanopolyhedra by using Raman scattering. The first-order CeO2 F-2g peak near 460 cm(-1) decreases when this reaction is fast (fast reduction and relatively slow reoxidation of the surface), because of the lattice expansion that occurs when Ce3+ replaces Ce4+ during oxygen vacancy creation. This shift correlates with reactivity for CO oxidation. Increases in the oxygen deficit delta as large as similar to 0.04 are measured relative to conditions when the ceria is not reduced.

引用

页码：12952 / 12955

页数：4

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