A simple synthesis of Fe2O3 powders and their structure, magnetic and electrical transport properties

Fe₂O₃ powders with highly crystalline have been synthesized by a sol-gel auto combustion synthesis method accompanying thermal process. The phase structures, morphologies of Fe₂O₃ have been characterized by x-ray powder diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy dispersive x-ray spectrometer (EDX). The results show that complete and highly crystalline nature magnetite powders can be obtained. Furthermore, the room-temperature magnetizations and the resistance of Fe₂O₃ powders were also measured. The maximum magnetization of sample S1, S2 and S3 is 88.3, 87.32 and 89.4emu/g at the applied magnetic field 5kOe, respectively, which are larger than the saturation magnetization of the bulk γ-Fe₂O₃ (76emu/g). It is proved further that Fe₂O₃ powders can be synthesized by the citrate-nitrate sol-gel auto combustion reaction method. The preliminary reaction mechanism is also discussed.