Single crystal ellipsoidal and spherical particles of α-Fe2O3: Hydrothermal synthesis, formation mechanism, and magnetic properties

Monodisperse ellipsoidal and spherical alpha-Fe2O3 particles have been successful prepared by hydrothermal synthetic route using FeCl3, NaOH, C2H2O4 as raw materials and reacting at 120 degrees C and 200 degrees C for 12 h. The morphology and structure of products were characterized by powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the ellipsoidal and spherical alpha-Fe2O3 particles were single crystalline rhombohedral and the average diameters were about 570 nm and 300 nm, respectively. Magnetic properties have been detected by a vibrating sample magnetometer at room temperature. The ellipsoidal and spherical particles exhibited a ferromagnetic behavior, which coercive force (Hc) were 3815.0 Oe and 1543.34 Oe, saturation magnetization (Ms) were 0.34 emu/g and 0.21 emu/g, remanent magnetization (Mr) were 0.16 emu/g and 0.10 emu/g, respectively. (C) 2013 Elsevier B.V. All rights reserved.