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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Effects of catalyst load in Pt and Pb-based catalysts using formic acid oxidation as a model

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Author(s):
Buzzo, G. S. [1] ; Orlandi, M. J. B. [1] ; Teixeira-Neto, E. [2] ; Homem-de-Mello, P. [1] ; Lopes, A. C. G. [1] ; Franco-Junior, E. [1] ; Suffredini, H. B. [1]
Total Authors: 7
Affiliation:
[1] Univ Fed ABC, Ctr Ciencias Nat & Humanas, Santo Andre, SP - Brazil
[2] Univ Sao Paulo, Dept Quim Fundamental, BR-05508000 Sao Paulo - Brazil
Total Affiliations: 2
Document type: Journal article
Source: Journal of Power Sources; v. 199, p. 75-84, FEB 1 2012.
Web of Science Citations: 5
Abstract

In this paper, we discuss the effects of catalyst load with respect to carbon powder for several Pt and Pb-based catalysts, using formic acid as a model molecule. The discussion is based on electrochemical tests, a complete morphological investigation and theoretical calculations. We show that the Pt and Pb-based catalysts presented activity in formic acid oxidation at very low catalyst loads (e.g., 0.5% in respect to the carbon content). Physical characterisations demonstrate that the electrodes are composed of separated phases of Pt and lead distributed in Pt nanometric-sized islands that are heterogeneously dispersed on the carbon support and Pb ultra-small particles homogeneously distributed throughout the entire carbon surface, as demonstrated by the microscopy studies. At high catalyst loads, very large clusters of Pb(x)O(y) could be observed. Electrochemical tests indicated an increase in the apparent resistance of the system (by a factor of 19.7 Omega) when the catalyst load was increased. The effect of lead in the materials was also studied by theoretical calculations (OFT). The main conclusion is that the presence of Pb atoms in the catalyst can improve the adsorption of formic acid in the catalytic system compared with a pure Pt-based catalyst. (C) 2011 Elsevier B.V. All rights reserved. (AU)

FAPESP's process: 07/05155-1 - Preparation and use of heterogeneous catalysts by the sol-gel method for electrocatalysis and biodiesel synthesis
Grantee:Hugo Barbosa Suffredini
Support Opportunities: Research Grants - Young Investigators Grants