Effect of synthesis route on the structural, optical and magnetic properties of Fe3O4 nanoparticles

Fe3O4 nanoparticles were prepared by the co-precipitation as well as combustion method. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–Visible spectroscopy and vibrating sample magnetometer (VSM) were used to study the physical properties. XRD pattern revealed the formation of single magnetite phase in the compound. TEM micrographs confirmed the uniform distribution of nanoparticles. UV–Visible spectroscopy measurement exhibited that the shifting of λmax with the variation of particle size which indicated that band gap is dependent on particle size. Development of well saturated magnetization loop indicated the magnetic nature of the samples. The as prepared Fe3O4 nanoparticles exhibited superparamagnetic behavior. The band gap as well saturation magnetization (Ms) was found to be strongly dependent on the particle size. The saturated magnetization of the superparamagnetic Fe3O4 nanoparticles prepared by the co-precipitation and combustion methods were found to be ∼63.5 emu/g and 44.2 emu/g, respectively at room temperature which enables them to be recycled from the solution by applying a small magnet.