Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1291759 | Journal of Power Sources | 2007 | 5 Pages |
Abstract
Electrocatalysis on the anode side of PEM fuel cells (PEMFC) has been widely studied, however, little information has been published on cermet catalysts, probably due to the very low or negligible power density registered when a ceramic oxide is blended with Pt based powders. In spite of this, there exists an advantage in the use of oxides, such as TiO2. This type of oxide can exhibit a bifunctional catalytical effect, as a Pt protecting matrix in the hydrogen oxidation reaction (H.O.R.) which increases CO oxidation and also promotes hydroxide formation, thus improving the oxidation of hydrogen. In this work, a trimetallic composition of 50Â mol% (Pt-Ru-Ni, 60:30:10)-50Â mol% TiO2 is investigated as anode catalyst for a PEMFC. For the preparation of this catalyst, combustion synthesis was the route selected, which allows us to achieve a powder composite with trimetallic (PtRuNi) and ceramic (TiO2) phases. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and polarisation curves (after MEA construction) are used to evaluate the catalytic activity of this type of powder. The catalyst obtained shows a single trimetallic phase with an average particle size of 8Â nm. The TiO2 was found mainly as anatase phase with an average particle size of 2-3Â nm. No reaction was detected between the two phases. The high power density exhibited (107Â mWÂ cmâ2) with this cermet may be attributable to by a bifunctional effect on the CO and hydrogen oxidation reactions which occur during the single cell operation.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
B. Moreno, E. Chinarro, J.L.G. Fierro, J.R. Jurado,