Ethanol electrooxidation onto stepped surfaces modified by Ru deposition:: electrochemical and spectroscopic studies

被引:84
作者
Del Colle, V. [2 ]
Berna, A. [1 ]
Tremiliosi-Filho, G. [3 ]
Herrero, E. [1 ]
Feliu, J. M. [1 ]
机构
[1] Univ Alicante, Inst Electroquim, E-03080 Alicante, Spain
[2] Univ Estadual Alagoas, CEFET AL, BR-57312000 Poco, AL, Brazil
[3] Univ Sao Paulo, Inst Fis & Quim Sao Carlos, Dept Fisicoquim, BR-13560970 Sao Carlos, SP, Brazil
关键词
D O I
10.1039/b802683a
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
Oxidation of ethanol on ruthenium-modified Pt(775) and Pt(332) stepped electrodes has been studied using electrochemical and FTIR techniques. It has been found that the oxidation of ethanol on these electrodes takes place preferentially on the step sites yielding CO2 as the major final product. The cleavage of the C-C bond, which is the required step to yield CO2, occurs only on this type of site. The presence of low ruthenium coverages on the step sites promotes the complete oxidation of ethanol since it facilitates the oxidation of CO formed on the step from the cleavage of the C-C bond. However, high ruthenium coverages have an important inhibiting effect since the adatoms block the step sites, which are required for the cleavage of the C-C bond. Under these conditions, the oxidation current diminishes and the major product in the oxidation process is acetic acid, which is the product formed preferentially on the (111) terrace sites.
引用
收藏
页码:3766 / 3773
页数:8
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