De Resende, Valdirene Gonzaga and Peigney, Alain and De Grave, Eddy and Laurent, Christophe In situ high-temperature Mössbauer spectroscopic study of carbon nanotube-Fe-Al2O3 nanocomposite powder. (2009) Thermochimica Acta, vol. 494 (n° 1-2). pp. 86-93. ISSN 0040-6031
(Document in English)
PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Official URL: http://dx.doi.org/10.1016/j.tca.2009.04.024
The oxidation of a carbon nanotube–Fe–Al2O3 nanocomposite powder was investigated using notably thermogravimetric analysis, room temperature transmission and emission Mössbauer spectroscopy and, for the first time, in situ high-temperature transmission Mössbauer spectroscopy. The first weight gain (150–300 °C) was attributed to the oxidation into hematite of the α-Fe and Fe3C particles located at the surface and in the open porosity of the alumina grains. The 25 nm hematite particles are superparamagnetic at 250 °C or above. A weight loss (300–540 °C) corresponds to the oxidation of carbon nanotubes and graphene layers surrounding the nanoparticles. The graphene layers surrounding γ-Fe–C particles are progressively oxidized and a very thin hematite layer is formed at the surface of the particles, preventing their complete oxidation while helping to retain the face-centered cubic structure. Finally, two weight gains (670 and 1120 °C) correspond to the oxidation of the intragranular α-Fe particles and the γ-Fe–C particles.
|Additional Information:||Thanks to Elsevier editor. The definitive version is available at http://www.sciencedirect.com The original PDF of the article can be found at Thermochimica Acta website : http://www.sciencedirect.com/science/journal/00406031|
|Audience (journal):||International peer-reviewed journal|
|Institution:||French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)|
Université de Toulouse > Institut National Polytechnique de Toulouse - INPT (FRANCE)
Université de Toulouse > Université Paul Sabatier-Toulouse III - UPS (FRANCE)
?? univ-ghent ??
|Deposited By:||Nihad Lahdifi|
|Deposited On:||23 Feb 2011 10:18|
Repository Staff Only: item control page