TEA controllable preparation of magnetite nanoparticles (Fe3O4 NPs) with excellent magnetic properties

•The Fe3O4 NPs are synthesized by a simple and low-cost hydrothermal approach.•The triethanolamine (TEA) played vital roles in the formation of Fe3O4 NPs.•Our samples exhibited superparamagnetic and excellent dispersing properties in water.

A fast and controllable synthesis method for superparamagnetic magnetite nanoparticles (Fe3O4 NPs) was developed in Fe(III)-triethanolamine (TEA) solution. The phase structure, morphology and particle size of the as-synthesized samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results showed that the magnetic particles were pure Fe3O4 with mean sizes of approximately 10 nm. The used TEA has key effects on the formation of well dispersing Fe3O4 NPs. Vibrating sample magnetometer (VSM) result indicated that the as-obtained Fe3O4 NPs exhibited superparamagnetic behavior and the saturation magnetization (Ms) was about 70 emu/g, which had potential applications in magnetic science and technology.