ESR study of the thermal decomposition of V-containing layered double hydroxides

Heat treatment induced transformations of the ESR signals present in the la yered double hydroxides (LDHs) containing vanadium (introduced either as an interlayer decavanadate anion or as a layer-forming cation) are investigat ed, with particular stress on the changes in the content, electronic struct ure and symmetry of the vanadyl species created. The differences in the cat alytic activity in the oxidative dehydrogenation of propane of the mixed ox ide materials resulting from the decomposition of the investigated LDHs are related to the differences in the degree of in-plane pi-covalent bonding o bserved for V(IV) centres present in these materials. (C) 1999 Elsevier Sci ence B.V. All rights reserved.