Direct thermal decomposition synthesis and characterization of hematite (α-Fe2O3) nanoparticles

Abstract

Hematite (α-Fe2O3) nanoparticles were prepared via direct thermal decomposition method using γ-Fe2O3 as a wet chemically synthesized precursor. The precursor was calcinated in air at 500°C. Samples were characterized by Thermogravimetric analysis (TGA), X-ray diffraction, Infrared, Scanning electron microscopy, Transmission electron microscopy (TEM) and Photon correlation spectroscopy (PCS). TEM and PCS analyses revealed that the average particle size of the α-Fe2O3 nanoparticles synthesized at 500°C are about 18±2nm and 50±3nm for 1h and 24±2nm and 82±3nm for 2h, respectively. The difference in average particle size determined by PCS and TEM analysis is due to the electrostatic forces between particles, and their agglomeration in PCS analysis. Magnetic properties have been detected by a Vibrating sample magnetometry at room temperature. The α-Fe2O3 nanoparticles exhibited a weak ferromagnetic behavior at room temperature.