Effect of Zn²⁺–Ti⁴⁺ co-doping on the structural, infrared, surface, magnetic, electric and dielectric parameters of nanoscale CoFe₂O₄

The nanospinel ferrites co-doping with different valence ions have gained lot of interest in the last some years. In this study, we report influence of Zn²⁺–Ti⁴⁺ co-doping on the structural, infrared, surface, magnetic, electric and dielectric parameters of nanoscale cobalt ferrite (CoFe₂O₄). The series of the nanoparticles with generic composition as CoFe_2−2xZn_xTi_xO₄ nanoparticles were obtained by simple and robust sol gel auto combustion synthesis technique. The Rietveld refined X-ray diffraction (XRD) patterns of all the samples revealed single-phase cubic spinel structure belonging to the typical spinel ferrites. Morphological analysis of the typical samples showed spherical shape like morphology with nanosize grains. Infrared studies reflected the occurrence of Me–O bond with two characteristics frequency bands analogous to octahedral and tetrahedral sites. The surface area values determined through BET analysis was found to be 34 m²/gm to 44 m²/gm. The M-H plots indicated ferrimagnetism with soft magnetic behaviour for all samples. The coercivity values were significantly decreased with increase in Zn²⁺–Ti⁴⁺ co-doping in cobalt ferrite. The electrical studies showed increasing trend with increase in Zn²⁺–Ti⁴⁺ co-doping for the resistivity. The dielectric analysis indicated the decreasing trend with increasing frequency as well as increase in Zn²⁺–Ti⁴⁺ co-doping. The co-doping of Zn²⁺–Ti⁴⁺ ion directs to the intriguing transformation in the features of cobalt ferrite nanoparticles appealing it for numerous application, for example, high frequency device applications, magnetic storage devices, biomedical field etc.