XPS characterization of nickel-acetylacetonate impregnated in NaX and NaY zeolites

Nickel supported species obtained by impregnation of Ni(acac)(2) onto faujasite zeolite (NaX and NaY) were identified by XPS and the influence of the nature of the support has been correlated with the location of the species in/on the zeolite. In the case of NaX two species are formed, one characterized by binding energy of 856.3 eV and ascribed to Ni(acac)(2) interacting with the support and the other with binding energy of 853.4 eV, similar to NiO. In the case of NaY only one species with BE of 854.4 eV is observed and has been ascribed to a nickel complex with one acac and oxygen of the framework of the zeolite as ligands. Ni(acac)(2) interacts differently with NaX and NaY according to the (Si/Al) ratio. Collapse of the NaX zeolite upon impregnation has been identified by textural analysis and related with the presence of more basic oxygen in its structure. (C) 2004 Elsevier Inc. All rights reserved.