SYNTHESIS AND MAGNETIC CHARACTERIZATION OF MAGNETITE PARTICLES EMBEDDED IN MESOPOROUS MCM-41.

N.A FELLENZ., S.G MARCHETTI., J.F. BENGOA, R.C. MERCADER AND S.J. STEWART.

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

Elsevier

Lugar: North-Holland; Año: 2006 vol. 306 p. 30 - 34

0304-8853

A solid of 7.7wt% iron-loaded MCM-41 was obtained by impregnating the mesoporous material with an Fe-carrying organic salt after subjecting the matrix to a silylation treatment. The Mössbauer and magnetic results show that the as-prepared composite is mainly made up of fine Fe3O4 particles that display a superparamagnetic relaxation at room temperature and block at » 42 K. A percentage of » 24% of the iron-containing phases is magnetically blocked at room temperature, and belongs to Fe3O4 that undergoes the Verwey transition. In addition, there is a minor Fe(III) phase that remains paramagnetic down to 4.2 K. r 2006 Elsevier B.V. All rights reserved. PACS: 75.30.Cr; 75.50.Tt; 75.60.Ej Keywords: Magnetically ordered materials; Nanostructures; Chemical synthesis; Nanofabrications; Magnetic nanoarrays synthesis; Fe3O4; MCM-41; Nanoparticles magnetism; Silylated mcm-41