16O/18O isotopic exchange:: A powerful tool to investigate oxygen activation on M/CexZr1-xO2 catalysts

被引:23
作者
Bedrane, S [1 ]
Descorme, C [1 ]
Duprez, D [1 ]
机构
[1] Univ Poitiers, CNRS, UMR 6503, Catalyse Chim Organ Lab, F-86022 Poitiers, France
关键词
isotopic exchange; three-way catalysts; oxygen activation; rhodium; platinum; palladium; ruthenium; iridium; ceria; ceria-zirconia;
D O I
10.1016/j.apcata.2005.04.016
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
Two series of metal catalysts (Rh, Pt, Pd, Ru and Ir) supported over CeO2 and Ce0.63Zr0.36O2 were prepared. Catalysts were pretreated at 500 degrees C (fresh) and further sintered either in H-2 or in air at 700-900 degrees C. All catalysts were characterized by H2 chemisorption at -85 degrees C and/or by transmission electron microscopy (TEM). The O-16(2)+O-18(2) homoexchange reaction was carried out in the 200-500 degrees C temperature range. Rh, Ru and Ir showed the highest homoexchange rate R (per M metal) while Pd and to a lower extent Pt were less active. Sintering affected the metal performances differently: while R is higher on small Rh particles (fresh catalysts), the reverse situation could be observed for Ru and Ir where the sintered catalysts were more active than the fresh ones, especially in the case of CeO2. (c) 2005 Elsevier B.V. All rights reserved.
引用
收藏
页码:90 / 96
页数:7
相关论文
共 38 条
[1]  
[Anonymous], 1990, MAT CONCEPTS SURFACE
[2]   Investigation of the oxygen storage process on ceria- and ceria-zirconia-supported catalysts [J].
Bedrane, S ;
Descorme, C ;
Duprez, D .
CATALYSIS TODAY, 2002, 75 (1-4) :401-405
[3]   Towards the comprehension of oxygen storage processes on model three-way catalysts [J].
Bedrane, S ;
Descorme, C ;
Duprez, D .
CATALYSIS TODAY, 2002, 73 (3-4) :233-238
[4]   An optimized route for the preparation of well dispersed supported ruthenium catalysts [J].
Bedrane, S ;
Descorme, C ;
Duprez, D .
JOURNAL OF MATERIALS CHEMISTRY, 2002, 12 (05) :1563-1567
[5]   Nanostructural evolution of a Pt/CeO2 catalyst reduced at increasing temperatures (473-1223 k): A HREM study [J].
Bernal, S ;
Calvino, JJ ;
Gatica, JM ;
Larese, C ;
LopezCartes, C ;
PerezOmil, JA .
JOURNAL OF CATALYSIS, 1997, 169 (02) :510-515
[6]   MICROSTRUCTURAL AND CHEMICAL-PROPERTIES OF CERIA-SUPPORTED RHODIUM CATALYSTS REDUCED AT 773-K [J].
BERNAL, S ;
BOTANA, FJ ;
CALVINO, JJ ;
CAUQUI, MA ;
CIFREDO, GA ;
JOBACHO, A ;
PINTADO, JM ;
RODRIGUEZIZQUIERDO, JM .
JOURNAL OF PHYSICAL CHEMISTRY, 1993, 97 (16) :4118-4123
[7]   HREM STUDY OF THE BEHAVIOR OF A RH/CEO2 CATALYST UNDER HIGH-TEMPERATURE REDUCING AND OXIDIZING CONDITIONS [J].
BERNAL, S ;
BOTANA, FJ ;
CALVINO, JJ ;
CIFREDO, GA ;
PEREZOMIL, JA .
CATALYSIS TODAY, 1995, 23 (03) :219-250
[8]   The dynamics of oxygen storage in ceria-zirconia model catalysts measured by CO oxidation under stationary and cycling feedstream compositions [J].
Boaro, M ;
de Leitenburg, C ;
Dolcetti, G ;
Trovarelli, A .
JOURNAL OF CATALYSIS, 2000, 193 (02) :338-347
[9]  
BORESKOV GK, 1964, ADV CATAL, V15, P285
[10]   Infrared study of oxygen adsorption and activation on cerium-zirconium mixed oxides [J].
Descorme, C ;
Madier, Y ;
Duprez, D .
JOURNAL OF CATALYSIS, 2000, 196 (01) :167-173