Synthesis and magnetic characterization of magnetite particles embedded in mesoporous MCM-41

• DOI: 10.1016/j.jmmm.2006.02.101
• Publication Date: 2006-03-14T13:48:09Z
• Authors: Nicolás A. Fellenz; Sergio G. Marchetti; José F. Bengoa; Roberto C. Mercader; Silvana J. Stewart
• Keywords: Magnetic Nanoarrays Synthesis; Fe3o4; Silylated Mcm-41; Chemical Synthesis; 02 engineering and technology; Nanofabrications; Nanostructures; Magnetically Ordered Materials; https://purl.org/becyt/ford/1.3; Nanoparticles Magnetism; https://purl.org/becyt/ford/1; 0210 nano-technology; Mcm-41

Abstract A solid of 7.7 wt% 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 Mossbauer and magnetic results show that the as-prepared composite is mainly made up of fine Fe 3 O 4 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 Fe 3 O 4 that undergoes the Verwey transition. In addition, there is a minor Fe(III) phase that remains paramagnetic down to 4.2 K.