Multifunctional rare earth or bismuth oxide materials for catalytic or electrical applications
1 Institut Matériaux Microélectronique et Nanosciences de Provence, IM2NP, UMR CNRS 7334, Université du Sud Toulon-Var, BP. 20132, 83957 La Garde Cedex, France
2 Laboratoire Matériaux et Environnement LME, Faculté des Sciences, Université Ibn Zohr, BP. 8106, Cité Dakhla, Agadir, Maroc
a e-mail: firstname.lastname@example.org
We present a review on catalytic or electrical properties of materials based on rare earth (RE) oxides (CeO2, La2O3, Lu2O3) or bismuth based composite systems CeO2-Bi2O3, susceptible to be integrated into catalytic microsystems or gas sensors. The polycrystalline solids can be used as catalysts allowing conversion of CO or CH4 traces in air-gas flows. Fourier Transform infrared spectroscopy is used to determine the conversion rate of CO or CH4 into CO2 through the variations versus time and temperature of vibrational band intensities. The time dependent reactivities are interpreted in terms of an adapted Avrami model. In these catalytic analyses the nature of surfaces of polycrystalline solids seems to play a prominent role in catalytic efficiency. Electrical impedance spectroscopy allows analyzing the variation of conductivity of the system CeO2-Bi2O3. In this system, the specific high ionic conduction of a Bi2O3 tetragonal phase might be linked to the high catalytic activity.
© Owned by the authors, published by EDP Sciences, 2013
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.