BIMETALLIC REFORMING CATALYSTS - EXAFS INVESTIGATION OF THE PARTICLE-GROWING PROCESS DURING THE REDUCTION STEP

被引：40

作者：

BAZIN, D ^{[1
]}

DEXPERT, H ^{[1
]}

BOURNONVILLE, JP ^{[1
]}

LYNCH, J ^{[1
]}

机构：

[1] INST FRANCAIS PETR,F-92506 RUEIL MALMAISON,FRANCE

来源：

JOURNAL OF CATALYSIS | 1990年 / 123卷 / 01期

关键词：

D O I：

10.1016/0021-9517(90)90159-H

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：

EXAFS has been used to study the reduction which leads to the active species of PtRh and PtRe reforming catalysts. The first moments of the formation of the metallic cluster have been followed kinematically at the platinum absorption edge for two catalysts, PtRh/γ-Al2O3 and PtRe/γ-Al2O3, using two different modes for the EXAFS setup (different synchrotron stations). The experiments have been made in situ, the sample being under flowing hydrogen at high temperature. The main result is the appearance of long metal-metal distances, of the same range order as that of the bond lengths existing in the alumina network. They occur solely for a very low number of metal atoms and are probably due to an intergrowth process with the carrier. The phenomenon seems to be general and disappears with the growth of the particle. © 1990.

引用

页码：86 / 97

页数：12

共 29 条

[1] EXTENDED X-RAY-ABSORPTION FINE-STRUCTURE OF SMALL CU AND NI CLUSTERS - BINDING-ENERGY AND BOND-LENGTH CHANGES WITH CLUSTER SIZE [J].