Structural, microstructural and surface properties of a specific CeO2–Bi2O3 multiphase system obtained at 600°C

Time-Dependent Oxidative Capacities of La2O3, Lu2O3Bakiz1, Bourja2, Benlhachemi3 et al. 2012ISRN Materials ScienceSelf Cite1100View full textAdd to dashboardCite

“…In the case of our previous studies on the system Bi 2 O 3 -CeO 2 [1], we clearly observed a high catalytic activity of the bismuth oxide interacting with air-CO gas flows and a poor activity of this oxide in presence of air-CH 4 gas flows.…”

“…To follow the reaction processes, we make use of Fourier transform infrared spectroscopy and determine the time-(t) and temperature-(T) dependent intensities I(t, T) of CO 2 vibrational bands resulting from the oxidation processes of CH 4 or CO in air-CH 4 or air-CO gas flows. In this study, we determine the catalytic efficiencies of La 2 O 3 , Lu 2 O 3 , CeO 2 , and Bi 2 O 3 polycrystalline oxides as a function of reaction time, at various temperatures: the air-CH 4 or air-CO flows cross through porous polycrystalline walls of these rare earth-based oxides and a system based on the Bi 2 O 3 phase [1].…”

Multifunctional rare earth or bismuth oxide materials for catalytic or electrical applications

“…Figures 1 and 2 show the evolutions versus temperature of vibrational band intensities I(t,T) of CO 2 gas formed from CO or CH 4 oxidations after a long oxidation period. In contradiction with theoretical predictions, a strong reactivity of lutetium oxide has been observed [3].…”

“…In the case of RE oxide [1,2] and CeO 2 -Bi 2 O 3 materials [3,4], infrared spectroscopy as a function of time (t) and temperature (T) has been used to determine the catalytic oxidation rates of CH 4 or CO into CO 2 . In the case of bismuth based system [(1 − x)CeO 2 − (x/2)Bi 2 O 3 ] with 0 < x < 1, electrical impedance spectroscopy (EIS) has been used to determine the conductivities as a function of bismuth fraction (x) and temperature (T).…”

Gd–Bi–Ce–O materials as catalysts in CO oxidation

“…Another way is proposed for the production of materials based on ceria and bismuth oxide, since dBi 2 O 3 has the highest ionic conductivity among all available oxides. As the content of bismuth oxide increases, the electrical conductivity also increases, but an additional tetragonal phase Bi 2 O 3 in Bi x Ce 1-x O 2 (for x C 0.2-0.3) also occurs, which affects the stability of such systems, and therefore the electrical conductivity and the catalytic activity in general (Bourja et al 2011;Prekajski et al 2013;Prekajski et al 2014;Bourja et al 2010). However, solid solutions of Gd-Bi-Ce-O were not previously proposed either as catalysts or as electrolytes.…”