An analysis of X-ray absorption spectra in the XANES region of platinum-based electrocatalysts for low-temperature fuel cells

被引：19

作者：

Sousa, Ruy, Jr. ^{[1
]}

Colmati, Flavio ^{[1
]}

Ciapina, Eduardo Goncalves ^{[1
]}

Gonzalez, Ernesto Rafael ^{[1
]}

机构：

[1] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13560970 Sao Carlos, SP, Brazil

来源：

JOURNAL OF SOLID STATE ELECTROCHEMISTRY | 2007年 / 11卷 / 11期

关键词：

platinum catalysts; electrocatalysis; X-ray absorption; XANES;

D O I：

10.1007/s10008-007-0354-9

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

The knowledge of the electronic state of Pt-based electrocatalysts used in low temperature fuel cells is very important for the understanding of the activity of the material. Near-edge X-ray absorption spectroscopy (XANES), a particular region of the X-ray absorption spectra (XAS), can provide the desired information, but the analysis is not straightforward, particularly for the non-specialist. Mansour et al. (J. Phys. Chem., 88:2330, 1984) and Shukla et al. (J. Electroanal. Chem., 563:181, 2004) presented methods to obtain information on electronic states from XANES spectra. In this work, procedures to implement the two methods are presented in detail and applied to XANES results for Pt2Sn1/C and Pt/C electrocatalysts prepared in this laboratory. The scope and limitations of the two methods are also discussed. The results show that the presence of Sri in the Pt2Sn1/C material promotes a partial filling of the Pt 5d band, in comparison to Pt/C, which contributes to explain the better activity of the bimetallic material.

引用

页码：1549 / 1557

页数：9

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