Structural and magnetic characterization of MnxZn1 − xFe2O4 (x = 0.2; 0.35; 0.65; 0.8; 1.0) ferrites obtained by the citrate precursor method

In this work the microstructure and magnetic properties of Mn–Zn ferrites powders were investigated. MnxZn1 − xFe2O4 powders where x = 0.2; 0.35; 0.5; 0.65; 0.8 and 1.0 were obtained by citrate precursor method. Citrate resin precursor was burned on air atmosphere at 400 °C for 3 h. Mn–Zn powders were calcined at 950 °C during 150 min under inert atmospheres: N2 and rarefied atmosphere. Thermal analysis of precursor resin, phase evolution and microstructure of Mn–Zn ferrites powders were investigated by TG, DTA, XRD and SEM techniques. The powders calcined under rarefied atmosphere show spinel cubic structure and contamination of α-Fe2O3, while powders calcined under N2 presents only the spinel cubic structure. Particle size was observed by SEM ranging from 80 to 150 nm. The magnetic properties were measured employing a vibrating sample magnetometer (VSM). It was observed that the saturation magnetization Ms increased with the increase of Mn content. The Ms of Mn0.8Zn0.2Fe2O4 calcined on rarefied atmosphere and Mn0.8Zn0.2Fe2O4 calcined on N2 was 23.31 emu g−1 and 56.23 emu g−1, respectively.