Manifestation of Magnetic Characteristics of Zinc Ferrite Nanoparticles Using the Langevin Function.

Zinc ferrite (ZnFe2O4) nanoparticles were prepared by chemical co-precipitation method. Structural characterization was performed using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Formation of spinel phase was confirmed from XRD studies. Crystallite size and lattice constant of the prepared sample were calculated. TEM images reveal spherical-shaped particles with nanosized distribution. Room temperature magnetic hysteresis loop was recorded using vibrating sample magnetometer (VSM). The magnetization loops exhibit a very narrow loop and behave like superparamagnetic nature. Using the Langevin function, the magnetic behaviour of the prepared nanoparticles was investigated. From the curve fitting, saturation magnetization and reduced magnetization were determined. As-prepared sample was further annealed at three different temperatures namely 800 °C, 1000 °C, and 1200 °C for 2-h duration. The effects of annealing on the structural and magnetic properties were further investigated using XRD and VSM. The observed results on the magnetic characteristics of ZnFe2O4 and applicability of the Langevin function are being discussed. [ABSTRACT FROM AUTHOR]