EFFECTS OF GAMMA AND NEUTRON IRRADIATIONS ON THE PHYSICAL, MAGNETIC AND ELECTRIC PROPERTIES OF Co-Cu-Cd AND Ni-Cu-Cd NANOFERRITES

Abstract

Irradiation effects on the structural, magnetic and electrical properties obtained by the sol-gel auto combustion synthesized Co0.3Cu0.2Cd0.5Fe2O4 and Ni0.3Cu0.2Cd0.5Fe2O4 nanoparticles by gamma (γ) and neutron irradiations are studied in the present research. The neutron irradiation of the samples has been done through neutrons (1.50X1012 cm-2 s-1 and 6.107×1013 cm-2 s-1 thermal neutron flux) from the TRIGA MARK-II research reactor and gamma irradiation by 64 KCi cylindrical 60Co source at room temperature (with doses of 1 MRad and 3 MRad at a dose rate of 0.1067 MRad/h) [for abstract the texts inside the first bracket may be omitted). XRD results show the stable spinel structure formation of the samples for the irradiation doses. The lattice constant (a0) of the investigated samples has been increased with the increase of irradiation (neutron/gamma) due to the conversion of Fe3+ (0.67 Å) to Fe2+ (0.76 Å). Due to the redistribution of ions, changes in the lattice constant have been found by the irradiation through the results of the XRD and Rietveld refinement process. The saturated magnetization obtained from the VSM is found to changes and further analyzed by LAS. The frequency-dependent characteristics such as dielectric constant, electric modulus, impedance analysis and ac conductivity are inspected for all samples with both types of irradiation process. The electrical modulus spectroscopy ensures the dominant property as electric stiffness for investigated ferrite nanoparticles. Cole-Cole plots for the complex impedance analysis suggest the predominant contribution to conduction was through the grain boundary. In this study, electrical and dielectric properties have been carried out with the influence of gamma and neutron irradiations which can be interpreted by the existing theories.