CeO2–La2O3 catalytic system. Part I. Preparation and characterisation of catalysts

Abstract

The CeO2–La2O3 catalytic system was prepared by a sol–gel technique from inorganic precursors in the presence or absence of H2O2 . Samples were characterised by means of nitrogen physisorption, TG-DTA, XRD, IR, XPS and TEM. Preparation ia sol–gel in the presence of H2O2 produces certain interesting modifications in CeO2–La2O3, both structurally and morphologically. Higher surface areas have been found for the CeO2–La2O3 system prepared in the presence of H2O2. On the other hand, for La2O3 the structure obtained upon calcination at 873 K corresponds to La(OH)3, and for the system prepared with hydrogen peroxide, to a mixture of La(OH)3, and La2O3 which was detected by XRD. Interesting morphological differences were observed for both systems.