Synthesis, Characterization, and Magnetic Studies of α-Fe2O3 Nanoparticles

Abstract

Very fine nanosized metal oxide, namely, iron oxide (α-Fe2O3) has been synthesized by precipitation method using ammonia as precipitating agent and characterized by using XRD (X-ray diffraction), TGA/DTA, surface area measurement, transmission electron microscopy (TEM), and magnetic measurements techniques. XRD studies show that iron oxide was formed as α-Fe2O3 instead of the commonly formed magnetite nanoparticles (Fe3O4) or a mixture of magnetite (Fe3O4) and maghemite (γ-Fe2O3, cubic), and it has rhombohedral structure. Magnetic measurements showed that iron oxide has five unpaired electrons and is ferromagnetic in nature, Ms value being 1.7 emu/g. The particle size of the synthesized iron oxide was determined by TEM. TEM images show that the size of particles of Fe2O3 varied from 15 nm to 49 nm with average crystallite size 35 nm.