%0 Journal Article 
%A Aberkane, Amar Bendieb
%A Yeste Sigüenza, María del Pilar
%A Fayçal, Djazi
%A Goma Jiménez, Daniel
%A Cauqui López, Miguel Ángel
%T Catalytic Soot Oxidation Activity of NiO–CeO2 Catalysts Prepared by a Coprecipitation Method: Influence of the Preparation pH on the Catalytic Performance
%D 2019
%@ 1996-1944
%U http://hdl.handle.net/10498/22119
%X A series of NiO–CeO2 mixed oxide catalysts have been synthesized by a modified
coprecipitation method at three di erent pH values (pH = 8, 9, and 10). The NiO–CeO2 mixed oxide
samples were characterized by TGA, XRD, inductively coupled plasma atomic emission spectroscopy
(ICP-AES), FTIR, Brunauer–Emmett–Teller (BET) surface area, H2 temperature-programmed
reduction (H2-TPR), and electron microscopy (high-angle annular dark-field transmission electron
microscopy/energy-dispersive X-ray spectroscopy (HAADF-TEM/EDS)). The catalytic activities of the
samples for soot oxidation were investigated under loose and tight contact conditions. The catalysts
exhibited a high BET surface area with average crystal sizes that varied with the pH values. Electron
microscopy results showed the formation of small crystallites (~5 nm) of CeO2 supported on large
plate-shaped particles of NiO (~20 nm thick). XRD showed that a proportion of the Ni2+ was
incorporated into the ceria network, and it appeared that the amount on Ni2+ that replaced Ce4+ was
higher when the synthesis of the mixed oxides was carried out at a lower pH. Among the synthesized
catalysts, Ni-Ce-8 (pH = 8) exhibited the best catalytic performance.
%K nickel
%K cerium
%K coprecipitation
%K soot oxidation
%K mixed oxides
%~ Universidad de Cádiz