Iron oxide nanoparticles supported on mesoporous MgO and CeO2:: A comparative physicochemical and catalytic study

Iron (III) containing nanoparticles with superparamagnetic behaviour are prepared via deposition on various mesoporous supports (MgO, CeO2 and SBA-15). XRD, TEM-EDX, N-2 physisorption, FTIR, and Moessbauer spectroscopy are used for their characterization. The reductive properties and catalytic behaviour in methanol decomposition of the materials are also studied. Depending on the chemical nature of the support, the predominant formation of: isolated iron species, strongly interacting with the support (for SBA-15), mixture of hematite and binary MgFe2O4 nanoparticles (for MgO) or almost homogeneously dispersed hematite particles (for CeO2) are observed. The state of iron species strongly affects their catalytic properties. The favorable effect of the support mesoporosity on the catalytic activity is most pronounced for the iron modified CeO2. (C) 2007 Elsevier Inc. All rights reserved.