Aging-induced metal redistribution in bimetallic catalysts

被引:14
作者
Graham, GW
Sun, H
Jen, HW
Pan, XQ
McCabe, RW
机构
[1] Ford Res Lab, Dept Chem Engn, Dearborn, MI 48121 USA
[2] Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA
关键词
aging; alloying; automotive exhaust catalysts; bimetallic catalysts; ceria-zirconia; oxygen storage; Pd-Rh; Pt-Rh; TEM;
D O I
10.1023/A:1016051821097
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
Alloy particles were detected by XRD in bimetallic catalysts, made from physical mixtures of powders comprising distinct metal-support combinations (e.g., Pd on alumina and Rh on ceria-zirconia), following high-temperature redox aging. The morphology of the catalysts was examined by TEM, and the compositional structure of some of the alloy particles was determined. Two different effects of the redistribution of metals on oxygen-storage capacity were identified, one due to Pd enrichment of the surface of Pd-Rh alloy particles and the other due to loss of contact between metal and ceria-zirconia.
引用
收藏
页码:1 / 7
页数:7
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