| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1338146 | Polyhedron | 2011 | 6 Pages |
Spinel ferrites of the composition Ni1−xCuxFe2O4 (x = 0.0–1.0) have been prepared through the thermal decomposition of their respective impregnated oxalates. The oxalate decomposition process was followed using differential thermal analysis–thermogravimetry techniques (DTA–TG). The synthesized nanocrystallites were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). The formation of single-phase ferrite is confirmed by XRD. Tetragonal deformation is observed for samples with composition x ⩾ 0.7. The increase in the lattice parameter with increasing Cu content can be explained based on the relative ionic radius. The TEM image shows spherically non-agglomerated particles with an average crystallite size that agrees well with that obtained from XRD. FT-IR studies show two absorption bands (ν1 and ν2) near to 600 and 400 cm−1 for the tetrahedral and octahedral sites, respectively. The hysteresis measurements were done using a vibrating sample magnetometer (VSM). The cation distribution in these compositions is calculated from the magnetization data. With increasing Cu content, the saturation magnetization (Ms) was observed to decrease while the coercivity (Hc) increases. The possible reasons responsible for the composition dependence of the magnetic properties were discussed. The Curie temperature, measured through the temperature dependence of the dc-molar magnetic susceptibility, was found to decrease with increasing Cu content.
Graphical abstractThe TEM image shows the nano-structured nature and spherical morphology of the Ni–Cu ferrite powder with uniform size. The particle size is about 50 nm. The synthesized powder is well dispersed without any aggregation.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Nano-sized Ni1−xCuxFe2O4 ferrites were prepared via the decomposition of oxalates. ► Effect of Cu2+ ion substitution on structural and magnetic properties was studied. ► The cation distribution was estimated using structural and magnetic properties.
