Mössbauer Investigation of of 7-Fe2O3 Nanocrystals in Silica Matrix Prepared by the Sol-gel Method

Abstract

A series of Fe2O3-SiO2 nanocomposites (25 weight % of Fe2O3) has been prepared using a sol-gel method. Samples showing different features were obtained by varying the evaporation conditions acting on the surface / volume ratio of the starting sol. The samples were investigated using Mössbauer spectroscopy at low temperature. The Fe2O3 nanoparticles have been identified as maghemite (7-Fe203) particles. The samples show a superparamagnetic behavior with a blocking temperature that depends on the average particle size. © 2014, Verlag der Zeitschrift für Naturforschung. All rights reserved.