STUDY ON SOME FACTORS OF MAGNETIC FLUID CHITOSANCOATED Fe3O4 NANOPARTICLES FABRICATION VIA HYDROTHERMAL METHOD

Abstract

To optimize reaction conditions of hydrothermal preparation of crystalline magnetite(Fe3O4) nanoparticles, the influence of some experimental parameters (temperature, initialconcentration of ferric and ferrous ions, and heating time), and their interactions on the magneticnanoparticle formation was studied using response surface methodology (RSM), based on astatistical design of experiments (DOE). The variation in the particle diameter and crystallitesize of obtained magnetic nanoparticles (MNPs) with the synthesis conditions was examined andtransmission electron microscopy (TEM) and X-ray diffraction analysis. The results showed thatcrystallite size was greatly affected by temperature, ferric salt concentration and the heatingtime, whereas the particle diameter strongly depended on the heating time, and on the interactionbetween the initial ferrous/ferric ion molar ratio and the initial concentration of ferrous ions. TheMNPs produced by this method were the objects to coat surface with chitosan solution. Thechitosan coated MNPs are nearly spherical with a mean size from 10 to 20 nm depending on theexperimental conditions. RSM analysis showed that under optimized conditions, the chitosancoated MNPs with smallest size 13.43 ± 1.5 nm and saturation magnetization 68.12 emu/g atroom temperature were obtained under the hydrothermal temperature 165oC, heating time 2 h 55minute and ferric salt concentration 0.21 M.