Cu2+- and Zn2+-doped cobalt spinel ferrite: insights on structural, thermal conduction, electric, magnetic and elastic properties

Abstract

M–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} (where M=Cu and Zn) nanoferrites were successfully prepared using the citrate auto-combustion technique. The main idea was drawn through a complete study of the structural, morphological, thermal, magnetic, and electrical properties. The obtain findings were explained in the light of incorporation both {mathrm{Cu}}^{2+} and {mathrm{Zn}}^{2+} ions in the Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} crystal. All the investigated samples were found to belong to space group (Fd-3m) and space group number (227). The crystallite size of the Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}, Cu–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}, and Zn–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} nanoparticles was found to be 8, 15, and 14, respectively. While, the lattice constants were 8.4 nm, 8.39 nm, and 8.42 nm, respectively. The doping exhibits enhancement of the elastic properties. Cu–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} shows young’ modulus at 278.97 GPa, while the shear modulus was 185.98 GPa, as highest obtained values compared to virgin and other doping samples. The highest saturation magnetization was observed for virgin sample, Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}, (56.1 emu/g) compared to it being 46.9 and 45 emu/g for Cu–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} and Zn–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}, respectively. The highest magnetic susceptibility (0.639) was obtained for Zn–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}. The thermal conductivity, thermal diffusivity, and specific heat of the prepared samples were investigated by the hot disk technique at room temperature. The results have shown an enhancement in the thermal properties of Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}-doped Zn and Cu rather than virgin Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}, predicting required thermal stability in the working devices. The Cu–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} sample exhibits the highest value of thermal conductivity (0.95 W/m k), thermal diffusivity (0.75 m {mathrm{m}}^{2}/s), and specific heat (0.85 Mj/{mathrm{m}}^{3} k) compared to (0.6 and 0.82 W/m k), (0.52 and 0.6 m {mathrm{m}}^{2}/s), and (0.62 and 0.72 Mj/{mathrm{m}}^{3} k) for Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} and Zn–Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}, respectively. The electrical conductivity and permittivity of all ferrite samples were enhanced by augmenting the temperature. The highest values were achieved for Co{mathrm{Fe}}_{2}{mathrm{O}}_{4} sample. The present Co{mathrm{Fe}}_{2}{mathrm{O}}_{4}-doped {mathrm{Cu}}^{2+} and {mathrm{Zn}}^{2+} ions offer a decent contender material with appealing characteristics suitable for different electronic applications.