Preparation and characterization of perovskite REFeO3 nanocrystalline powders

Combustion of nitrate-citrate gel was employed to prepare REFeO3 (RE=Y, La and Gd) nanocrystalline powders. The samples were characterized with X-ray diffraction (XRD) analysis, thermal analysis (TG/DTA) and transmission electron microscopy (TEM). LaFeO3 crystallites were directly obtained by the sol-gel combustion process, and orthorhombic YFeO3 and GdFeO3 were formed when annealed at 800 °C. The investigation of magnetic properties showed that YFeO3 and LaFeO3 exhibited ferromagnetic behavior, while GdFeO3 presented paramagnetic coupling. It was suggested that the Fe sublattice governed the magnetization process in YFeO3 and LaFeO3. The dominance of paramagnetic component from Gd was observed in GdFeO3.