Microstructural, magnetic, and hyperfine characterizations of Cu‐doped cobalt ferrite nanoparticles

Abstract We have investigated the structural and magnetic properties of polycrystalline Cu‐substituted cobalt ferrite (Cu x Co 1− x Fe 2 O 4 : x = 0.00, 0.15, 0.30, 0.45, 0.60) nanoparticles, synthesized via chemical coprecipitation method. The prepared samples were of single phase as confirmed by X‐ray diffraction analysis. The mean crystallite size ranged from 44 to 65 nm was obtained using Scherrer's formula. M‐T curves revealed that the Curie temperature of all the samples was above room temperature and it was found to decrease with increasing Cu concentration, which was supported by Mössbauer spectra. Field cooled (FC) hysteresis curves showed ferrimagnetic nature at 5 K and room temperature. It was observed that careful variation of Cu concentration in cobalt ferrite lead to weak A‐B interaction with tunable magnetic properties.