Synthesis of Fe3O4 nanocrystals using hydrothermal approach

Magnetite (Fe3O4) nanocrystals were synthesized using a facile hydrothermal method. FeCl2, FeCl3 and NaOH with a molar ratio of 1:2:8 were added into an autoclave and this was followed by heat treatment at elevated temperature (100, 150 and 200 °C). The produced results show that the average crystallite and the physical size of the resulting Fe3O4 nanocrystals increased with the hydrothermal temperature. The Fe3O4 nanocrystals exhibited superparamagnetic behavior. The saturation magnetization and coercivity of the produced nanocrystals also increased with the hydrothermal temperature.

► The crystallinity of Fe3O4 nanocrystals has been improved. ► The particle and crystallite size of nanocrystals are well-fitted with single crystal structure. ► The crystallite and physical sizes of the nanocrystals increased with hydrothermal temperature. ► The Ms and Hc of Fe3O4 nanocrystals enhanced with increase of hydrothermal temperature.