Novel synthesis of core-shell stured Fe3O4 via sodiumsilicate

Abstract

Fe3O4 nanoparticles are supermagnetic magnetic nanoparticles with high magnetic penetration, relatively weak magnetism residual and coercive power. The application of these nanoparticles by different industries such as magnet fluids, electronic devices, information storage and biomedical equipment has been of considerable concern for these unique characteristics. However, nanoparticles must have properties such as high chemical stability or excellent solution dispersibility in order to be successful in such applications. Fe3O4 nanoparticles have a cluster configuration that is chemically unstable. Furthermore, Fe3O4 nanoparticles have a chemically unstable cluster structure. The dispersion is unstable because the energy of the surface is high and the charging of the surface is low by the size of the nanoscale particle, indicating a problem with particles that may intermute the balance between the attraction and repulsive force of van der Waals. In order to resolve this problem, there is a method for creating a double layer on the surface of the core material so that the shell's surface properties can coexist while maintaining the core and the shell material's properties. Among the potential candidates for the construction of this core shell structure using Fe3O4, amorphous SiO2 is the most representative material. In this study , a novel technique of synthesis using silicate sodium (Na2SiO3) was proposed to produce nanoparticles structured with core-shell Fe3O4@SiO2. Na2SiO3, which can use a smaller volume of solvent than the commonly used silane counterpart tetraethyl ortho silicate (TEOS), has a high economic efficiency and is ideally suited for mass processing. The core-shell structured Fe3O4@SiO2 nanoparticles obtained by Na2SiO3 were reported to have a thickness range of 1 nm to 19 nm depending on apropriate pH conditions. According to the difference in the thickness of the SiO2 layer, changes in dispersion properties and intrinsic physical properties of the particles in the aqueous solution were investigated. Also, the particles forming the core shell with Na2SiO3 and the particles forming the core-shell structure using TEOS were compared and analyzed in detail.