Water-gas shift catalysis: kinetic isotope effect identifies surface formates in rate limiting step for Pt/ceria catalysts

被引:79
作者
Jacobs, G [1 ]
Khalid, S [1 ]
Patterson, PM [1 ]
Sparks, DE [1 ]
Davis, BH [1 ]
机构
[1] Univ Kentucky, Ctr Appl Energy Res, Lexington, KY 40511 USA
关键词
water-gas shift; LTS; ceria; platinum; kinetic isotope effect; DRIFTS;
D O I
10.1016/j.apcata.2004.03.048
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
In this investigation. isotope switching from H2O to D2O was used to validate the possibility that the decomposition of formate could be the rate limiting step for the water gas shift mechanism over metal promoted ceria, as was proposed earlier by Shido and Iwasawa. The surface species were followed stepwise by in-situ DRIFTS, while the conversion was monitored by GC to quantify the conversions. A normal kinetic isotope effect was observed, consistent with a link between the activation energy barrier of the rate limiting step and the breaking of the formate C-H bond. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:255 / 266
页数:12
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