Evidence of structural damage in Sm and Gd co-doped Mn-Zn ferrite ceramics due to high-energy gamma irradiation

We report the evidence of structural changes due to high energy gamma irradiation in Mn0.4Zn0.6SmxGdyFe2-(x+y)O4 (where x=y=0.01, 0.02, 0.03, 0.04 and 0.05) ferrites prepared by self-propagating high temperature synthesis method. The structural properties of the as prepared samples and the structural modifications to the samples after gamma irradiation were studied by X-ray diffraction (XRD), Mossbauer spectroscopy and Fourier Transform Infrared (FTIR) Spectroscopy at room temperature. The XRD patterns of the as prepared samples reveal the formation of mixed cubic spinel phase along with small amounts of alpha-Fe2O3, SmFeO3 and/or GdFeO3 impurity phases. All samples were exposed to gamma radiation dose of 50 kGy originating from a Co-60 source. Our results demonstrate that after gamma irradiation the structure and composition of the various phases in the sample were changed and more stable new phases like ZnFe2O4, alpha-Fe2O3 and MnO2 evolved. As a result the (magnetic) properties of the materials were also altered. Our observation of changes in structural and magnetic properties of the reported ferrites are important for understanding the stability and performance of the materials used in various devices, which are exposed to high energy gamma-rays. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.