Synthesis, characterization and magnetic properties of La3+ added Mg-Cd ferrites prepared by oxalate co-precipitation method

Nanosized powders of Mg-Cd-La ferrite synthesized by oxalate co-precipitation method using high purity sulphates are presented. The powder has been characterized by X-ray powder diffraction (XRD), infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The phase identification of powder reveals biphasic nature of materials. The lattice constant, X-ray and physical density, porosity, crystallite size, site radii and bond length were directly affected by addition of rare earth ion (La3+) in Mg-Cd ferrite. The crystallite size of the samples lies in the range 25.67-30.55 nm. FT-IR spectra show two absorption bands in the frequency range from 3.5 x 10(4) to 8.0 x 10(4) m(-1) which are attributed to stretching vibration of tetrahedral and octahedral complex Fe3+-O2- respectively. The addition of La3+ alters the characters of powder and decreases the grain size which suppresses the abnormal grain growth. The addition of La3+ resulted increase in saturation magnetization, remnant magnetization. 4 pi M-s and coercivity. Coercivity shows size dependent behavior. Such results are promising ones for high frequency applications. (C) 2010 Elsevier B.V. All rights reserved.