Hydrogen sorption properties of magnesium particles decorated with metallic nanoparticles as catalyst
Langue
en
Article de revue
Ce document a été publié dans
Journal of Alloys and Compounds. 2009, vol. 476, n° 1-2, p. 152-159
Elsevier
Résumé en anglais
Both hydrogen absorption and desorption, in the range 200–300 and 260–330 °C, respectively, of magnesium particles decorated with metallic nanoplots elaborated by Supercritical Fluid Chemical process are studied. The ...Lire la suite >
Both hydrogen absorption and desorption, in the range 200–300 and 260–330 °C, respectively, of magnesium particles decorated with metallic nanoplots elaborated by Supercritical Fluid Chemical process are studied. The absorption data are fitted using Avrami–Erofeev model to first order. Unexpectively, magnesium decorated with copper nanoparticles lead to relatively high rates of sorption (absorption rate at 300 °C and desorption rate at 330 °C of about 0.4 wt%H min<sup>−1</sup>) but its activation energy remains high (70 kJ mol<sup>−1</sup>). The presence at the interface of MgCu<sub>2</sub>, acting as a chemical link between the nanoCu and the magnesium particle could be responsible for such behavior. Palladium nanoparticles react with magnesium during cycling so that the catalytic effect is decreasing with cycling and finally does not exist anymore after 10 cycles. Finally, the best results are obtained for the nanocomposite of magnesium with nickel nanoparticles for which the sorption rates are comparable with the ones obtained for optimized BM samples with catalysts, but with a lower energy cost of the process.< Réduire
Mots clés en anglais
Nanoparticles
Magnesium
Supercritical fluid chemical deposition
Hydrogen sorption
Kinetics
Origine
Importé de halUnités de recherche