INFRARED STUDIES OF CO ADSORBED ON SUPPORTED PT CO CATALYSTS

被引：46

作者：

DEES, MJ ^{[1
]}

SHIDO, T ^{[1
]}

IWASAWA, Y ^{[1
]}

PONEC, V ^{[1
]}

机构：

[1] UNIV TOKYO,BUNKYO KU,TOKYO 113,JAPAN

来源：

JOURNAL OF CATALYSIS | 1990年 / 124卷 / 02期

关键词：

D O I：

10.1016/0021-9517(90)90199-T

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：

The IR spectra of CO adsorbed on aerosil-supported Pt, Co, and several PtCo bimetallics have been investigated. It is observed that the addition of Co to Pt causes a decrease in the IR band wavenumber from 2075 to 2040 cu-1 at a given coverage φ(CO). A decrease in the coverage φ(CO) of the Pt and PtCo bimetallic surfaces also gives rise to a red shift, down to 2040 cm-1. For this reason the effect of Co can be regarded as a geometric effect (dilution of the CO layer). The addition of Co to Pt results in the appearance of a second absorption maximum (above 2000 cm-1. at 2086-2083 cm-1. This maximum disappears relatively quickly following pretreatment in n-hexane. It is ascribed here to the adsorption of CO on smooth surfaces. The monometallic Co system differs considerably from the other systems in that (a) its surface is not blocked easily by n-hexane and (b) passing CO at elevated temperatures results in the formation of CO-carbonyl species. In the bimetallic catalysts no Co with this behavior (unalloyed Co) could be detected. © 1990.

引用

页码：530 / 540

页数：11

共 41 条

[1] THE DESORPTION OF CO FROM SMALL PT PARTICLES ON AL2O3 [J].