Effect of Thermal Treatment on the Structure, Microstructure and Magnetic Properties of Co-precipitated CoFe2O4 Nanoparticles

The exceptional chemical and structural stability and the fascinating magnetization effects of Cobalt ferrite, make it a promising candidate for various applications. In this paper, Cobalt ferrite (CoFe2O4) nanoparticles were synthesized by the chemical co-precipitation method and subsequently heat-treated at various temperatures. The elemental chemical composition, structure, morphology, and magnetic properties of the as-prepared cobalt ferrite nanoparticles and those obtained by heat-treating the former at different temperatures were characterized by energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), Fourier transforms infrared analysis (FTIR), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). All samples had a cubic spinal-type structure. The average particles size increased with heat treatment temperature; It ranged from similar to 15 to similar to 35 nm in the temperature range 400-800 degrees C. Magnetic measurements revealed that both saturation magnetization (M-s) and coercivity field (H-c) are reasonably high and were found to increase with increasing temperature. The magnetic behavior of our ferrites was correlated with the XRD and the TEM results.