Síntesis y Caracterización de Nanopartículas Magnéticas de Hierro (Magnetita).

Abstract

A synthesis and a characterization of Magnetic Nanoparticles of Iron (Magnetite (Fe2+Fe3+O4) were made in the following investigation through the chemical method of co-precipitation. An experimental design completely at random focused in the analysis of the variance was used. This method considers the following three controllable variables: stirring time, boiling temperature and the concentration of the reagents. All of this is applied to a chemical precursor, composed almost entirely of iron, in order to determine the changes in the variable. This response is defined as the size of the nanoparticle. Ten treatments with three replicas each one were established considering that the middle level is a standard reference of a synthesis made before according to the literature. Also, the highest, lowest and standard limits were compared in order to define the possible changes that may occur, focusing our attention in the analysis of the size of the nanoparticles. The characterization was made with the help of the infrared spectroscopy which showed the characteristic spectrum of the Magnetite at different intensities. In addition to other functional groups of interest, the ultraviolet- visible spectroscopy allowed us to determine the changes in the controllable parameters which affect in quantity and size the nanoparticles from one treatment to another. Finally, through the use of the Scanning Electron Microscopy, the stable chemical structure of each of the samples of Iron Oxide were obtained. Some nanoparticles of iron with amorphous structure similar to the spherical ones were found. These nanoparticles have a size variation in each one of the treatments which comprise between 20 and 40 nm with different populations and physical- chemical characteristics in each of the treatments proposed. It is recommended to provide the nanoparticles obtained with a practical use according to the size required.