Preparation and characterization of fibrous MnZn ferrite via a water-assisted solvothermal method

Abstract

MnZn ferrite fibers have received wide attentions due to their unique structures, properties and potential applications. However, there are relatively few synthetic routes for fabricating MnZn ferrite fibers, the morphology and particle size of fibers are not uniform by the existing methods. In this paper, MnZn ferrite fibers have been controllably synthesized by a water-assisted solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analyzer (TGA) and vibrating sample magnetometer (VSM) analyses. The effects of experimental parameters such as ratio of ethylene glycol (EG) and water, reaction time and temperature, and annealed temperature on crystalline structure, size and morphology of MnZn ferrite were discussed systematically. The results indicated that the optimum experimental conditions for the formation of fibrous MnZn ferrite with uniform fiber-like morphology, smooth surface and the largest aspect ratio (length to diameter ratio) were as follows: the volume ratio of EG/water was around 3:1, the reaction time and temperature were respectively around 24 h and 120 ℃, and the annealed temperature was 500 ℃ or so. Meanwhile, the related magnetic property was also investigated. The results demonstrated that MnZn ferrite fibers had ferromagnetic nature, the saturation and remanent magnetization and coercivity of them were respectively 6.5 emu/g, 0.23 emu/g and 161.5 Oe.