Correlation between structural phase transition and physical properties of Co 2+/Gd 3+co-substituted copper ferrite

The doping of the spinel ferrites with selective cations usually improves the properties of the parent ferrite. The effect of Co 2+ /Gd 3+ co -substitution on the microstructure, optical, and magnetic properties of Cu 1- x Co x Fe 2- x Gd x O 4 prepared by the citrate -nitrate auto -combustion synthesis was investigated. Characterization of the samples was performed with powder X-ray diffraction (XRD), Raman and Fouriertransform infrared (FTIR) spectroscopy, field -emission scanning electron microscopy, X-ray energydispersive spectroscopy, UV-Vis spectroscopy, and a vibrating sample magnetometer. The results of XRD, Raman, and FTIR analysis show a gradual structural phase transition from a tetragonal ( I 4 1 / amd ) structure to a cubic ( Fd 3 m ) structure. The bandgap energy of the studied samples is in a range of 1.57-1.75 eV with a minimum in sample x = 0.06 and then increases. Magnetic investigations show that the presence of Co 2+ /Gd 3+ cations in an octahedral site of the copper ferrite structure could increase saturation magnetization and coercive field from 567.9 Oe and 23.62 emu/g to 929.4 Oe and 28.27 emu/g, respectively. (c) 2023 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.