화학공학소재연구정보센터
Applied Surface Science, Vol.314, 592-598, 2014
Gadolinium doped cerium oxide for soot oxidation: Influence of interfacial metal-support interactions
The aim of the present investigation was to ascertain the role of Al2O3, SiO2, and TiO2 supports in modulating the catalytic performance of ceria-based solid solutions. In this study, we prepared nanosized Ce-Gd/Al2O3, Ce-Gd/SiO2, and Ce-Gd/TiO2 catalysts by a deposition coprecipitation method and evaluated for soot oxidation. The synthesized catalysts were calcined at two different temperatures to assess their thermal stability and extensively characterized by various techniques, namely, XRD, Raman, BET surface area, TEM, H-2-TPR, and UV vis DRS. XRD and TEM results indicate that Ce-Gd-oxide nanoparticles are in highly dispersed form on the surface of the supports. Raman results show a prominent sharp peak and a broad peak corresponding to the F-2g mode of ceria and the presence of oxygen vacancies, respectively. The presence of a significant number of oxygen vacancies in all samples is also confirmed from UV vis DRS measurements. The H2-TPR results suggest that Gd-doping facilitates the reduction of the materials and decreases the onset temperature of reduction. Among the prepared samples, Ce-Gd/TiO2 catalyst exhibited the highest activity, suggesting the existence of strong interfacial metal support interaction between the active metal oxide and the support. (C) 2014 Elsevier B.V. All rights reserved.