Preparation and characterization of superparamagnetic magnetite (Fe3O4) nanoparticles: A short review

Magnetic magnetite (Fe3O4) nanoparticles have attracted a great deal of attention in both fundamental research and practical applications over the past decades. Down to the nanoscale, superparamagnetic Fe3O4 nanoparticles with only a single magnetic domain exhibit high magnetic susceptibility, which provides a stronger and faster magnetic response. Their superparamagnetic properties together with other intrinsic properties such as low toxicity, high surface area-to-volume ratio and simple separation methodology, making them ideal for environmental remediation, biomedical, and agricultural applications. This review discusses three conventional wet chemical methods, including chemical co-precipitation, sol-gel synthesis and thermal decomposition for the preparation of superparamagnetic Fe3O4 nanoparticles with controlled size and magnetic properties. Nowadays, with the growing research interest in Fe3O4 nanoparticles, there is a great amount of researches reported on efficient routes to prepare size-controlled magnetic nanoparticles. Thus, this review is designed to report the recent information from synthesis to the characterization of Fe3O4 nanoparticles as well as the discussion of future perspective in this research area.