Investigation of Structural and Magnetic Effects of Cobalt Doping in ZnFe2O4 Nanoparticles

We study structural and magnetic properties of magnetic ceramic CoxZn1−xFe2O4 nanoparticles synthesized by the co-precipitation method and optimize its size and magnetic property for possible application in wastewater treatment. The effects of long stirring time under boiling condition and the introduction of the third metal ion to the structure are investigated. To study the microstructural and magnetic characteristic of the samples, X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FESEM) analyses are carried out. The diffracted peaks of XRD pattern confirm the formation of spinel phase. In addition, we study the effect of Co doping on the peak positions in the spinel structures. To evaluate crystallite size and other lattice parameters of the samples, we use the Rietveld method as a nearly exact approximation instead of Scherrer formula. Thus, the Rietveld refinement method has been utilized and structural and lattice parameters of the samples are extracted using Reflex program. In contrast with other works, our nanoparticles show superparamagnetic behavior, larger surface area, and better crystallinity with no calcination which originates from the condition of the synthesis method.