Synthesis of iron oxide nanocomposites using layered double hydroxides

In the present work, an original method for the preparation of oxide nanostructured materials is discussed. The method is based on chemical modification of anion-substituted layered double hydroxides (LDH). It combines the simplicity of chemical methods and the possibility to prepare nanostructures directly in the matrix. During chemical reactions of anions in the interlayer space of LDHs, the reaction zone is spatially constrained by the hydroxide layers, giving rise to the conditions similar to those in 2D nanoreactors, such as Langmuir-Blodgett films and self-assembling monolayers. It was found that chemical modification of intercalated LDHs results in the formation of iron oxide nanoparticles with different morphology and composition (alpha-Fe2O3, gamma-Fe2O3), depending on the composition of initial precursors and conditions of chemical modifications. Obtained nanostructures were investigated by X-ray diffraction, TEM and Mossbauer spectroscopy. (C) 2003 Elsevier B.V. All rights reserved.