Synthesis of magnetite (Fe3O4) nano particles via precipitation method and study of their stability in water media

In the present work, magnetite nano particles were synthesized by precipitation method in the presence of polyoxyethilen (80), sorbitan monoleate (Tween 80), surface modifier under N2 atmosphere, using Iron (II) chloride (FeCl2) and Iron (III) chloride (FeCl3) as starting materials. Then samples were dispersed in water media to investigate the stability. Structure, micro structure, magnetic and optical properties were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), UV-Vis spectrometry techniques. Results showed that synthesis in the presence of surface modifier increased the uniformity of spherical nano magnetite particles. Moreover, VSM results at room temperature showed that the samples were superparamagnet without hysteresis loop. Band gap of samples were estimated as 2.8 eV which was 0.1 eV, larger than for bulk samples. Nano particles were synthesized in the presence of 0.5 g/l Tween 80 showed the best stability in aqueous media.