Nanoscale magnetite: New synthesis approach, structure and properties

Abstract

Nanoscale magnetite (Fe3O4) (NM) is widely used for various industrial and biomedical applications. Nevertheless, the preparation of NM with desirable structure and properties by means of simple, rapid, and environmentally friendly synthesis remains a major challenge.In this study, NM was synthesized for the first time from a waste material, namely, water deironing sludge, using a novel “sharp high-temperature dehydration” (SHTDH) approach. The magnetite obtained was verified via Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction (XRD). XRD results revealed that the as-synthesized NM crystallites were 7 nm in size. The TEM images showed a hierarchical nanostructure characterized by primary nanoparticles (with an average size of 4.5 nm) and their secondary arrays (mean size 57 nm). The N2 adsorption–desorption measurements have enabled classify the NM material as nanoporous. According to the magnetic measurements, the synthesized NM exhibited superparamagnetic behavior.The findings suggest that the SHTDH is a facile, time-effective, and environmentally friendly approach for the synthesis of nanoparticles with ultrasmall sizes. Furthermore, it can provide a new pathway for the preparation of novel materials for various industrial and biomedical applications.