Crystal-growth kinetics of magnetite (Fe3O4) nanoparticles with Ostwald Ripening Model approach

Magnetite (Fe3O4) nanoparticles is a magnetic nanomaterial that have potential properties to be applied as drug delivery The purpose of this study was to determine the influence of time and temperature synthesis of magnetie characteristics and determine its crystal growth kinetics model with Ostwald ripening model approach. Magnetite nanoparticles synthesized from FeCl3, citrate, urea and polyethylene glycol with hydrothermal method at 180, 200 and 220 degrees C for 1,3,5,7,9 and 12 hours. Characterization by X-ray Diffraction (XRD) indicated that magnetite formed at temperatures of 200 and 220 degrees C. Magnetite crystallite diameter obtained was 10-29 nm. Characterization by Transmission Electron Mycroscope (TEM) shows that magnetite nanoparticles have uniform size and non-agglomerated. Core-shell shaped particles formed at 200 degrees C and 220 degrees C for 3 hours. Irregular shape obtained at 220 degrees C for 12 hour synthesis with particle diameter about 120 nm. Characterization using Vibrating Sample Magnetometer (VSM) shown that magnetite has super paramagnetism behaviour with the highest saturation magnetization (Ms) was 70.27 emu/g. magnetite crystal growth data at temperature of 220 degrees C can be fitted by Ostwald ripening growth model with growth controlled by the dissolution of surface reaction (n approximate to 4) with the percent error of 2.53%.