Room temperature synthesis and magnetic property studies of Fe3O4 nanoparticles prepared by a simple precipitation method

•Magnetite nanoparticles were prepared by a simple precipitation method.•The influence of surfactant on the particle size of the products was investigated.•The effects of time, solvent and magnetic field on the morphology were examined.

Magnetite (Fe3O4) nanoparticles were prepared by a simple precipitation method between Fe(NO3)3·9H2O and FeCl2·4H2O. The effects of surfactant, temperature, time, solvent and magnetic field on the morphology and particle size of the products were investigated. The magnetic properties of the product were investigated using an alternating gradient force magnetometer (AGFM). The Fe3O4 nanoparticles exhibit ferrimagnetism behaviour at room temperature, with a saturation magnetization of 38.7 emu/g and a coercivity of 0.78 Oe. Such a low coercivity is attributed to superparamagnetic (which is a size dependent) behaviour of Fe3O4 in nanoparticle scale.