Enhancement of magnetic, supercapacitor applications and theoretical approach on cobalt-doped zinc ferrite nanocomposites

Nanostructured zinc ferrite, cobalt ferrite, and cobalt-doped zinc ferrite were synthesized by using a simple co-precipitation method. Physico-chemical analyses were investigated by thermogravimetric and differential thermal analysis (TG/DTA) and X-ray diffraction (XRD) techniques. The TG/DTA study revealed the thermal transformation of metal hydroxide precursors. The XRD representation confirmed the cubic spinel structure of the cobalt-doped zinc ferrite nanoparticles. The Fourier-transform infrared spectrum, recorded to acquire the characteristic vibration mode of the metal oxides, was present in the composites. The analyzed morphology was confirmed by field-emission transmission electron microscopy and field-emission scanning microscopy, revealing a spherical structure with an agglomeration of nanocomposites. Analysis of the energy dispersive X-ray spectrum of the cobalt-doped zinc ferrite nanocomposites exposed the elemental features. The prepared nanocomposites were examined using a vibrating sample magnetometer, which showed the transformation of paramagnetic to ferromagnetic behavior. The specific capacitance of the three ferrites were calculated, and there was a noticeable enhanced specific capacitance of 218 Fg⁻¹ in Co_0.5Zn_0.5Fe₂O₄ at the scan rate of 10mV/s. In the present work, the mixed spinel structure of the nanocomposites revealed the magnetic and electrochemical properties. The prepared nanocomposites can be used in energy storage devices. The theoretical part was calculated by the density functional theory method, which was employed to study the structural, nonlinear optics, and physico-chemical parameters of CoZnFe₂O₄ NPs.