Structural rietveld refinement, morphological and magnetic features of Cu doped Co-Ce nanocrystalline ferrites for high frequency applications

Copper (Cu) substituted Co-Ce nanoferrites with nominal composition of Co1-xCux Ce-0.05 Fe1.95O4 (x = 0.00, 0.25, 0.50, 0.75, 1.00) were prepared by sol-gel route. The sintering of the Cu doped Co-Ce nanoferrites was done at 700 degrees C to investigate the desired properties of the Cu doped Co-Ce nanoferrites. The combination of transition metal (Cu) and rare earth (Ce) were employed to tailor the characteristics of the spinel ferrites. The constant ratio of rare earth and systematic doping of Cu in Co ferrite was incorporated to see the effects of these ions in spinel ferrite. FTIR, FESEM, XRD and VSM were used to study the vibrational bands, phase, morphology, structure and magnetic properties of the Cu doped Co-Ce spinel nanocrystalline ferrites respectively. Average crystallite size, volume, strain and lattice parameters were evaluated from XRD. Bulk, X-ray density, and porosity were increased with Cu doping in Co-Ce spinel ferrites. Rietveld refinement of the Cu doped Co-Ce nanoferrites was done using MAUD software. Site radii, shared and unshared edges, bond lengths due to the Cu substitution were also study by Bertaut technique. FTIR studies were done to find out the force constants and absorption bands at tetrahedral and octahedral sites. Magnetic loops were recorded from VSM and magnetic properties such as remanent magnetization, coercivity, saturation, magnetic anisotropy constant (K), initial permeability and Bohr magnetic moments were determined. Saturation, remanence, coercivity, Bohr magnetic moment and anisotropy constant of the Cu doped Co-Ce nanoferrites were decreased. However, Yafet-Kittel (Y-K) angles were found to be enhanced with Cu doped Co-Ce nanoferrites. High frequency response of the Cu doped spinel nanoferrites in microwave region was also evaluated using the saturation data of the samples. All the Cu doped Co-Ce nanoferrites samples are suggested to be used in microwave for X-band regime.