Effect of Ambient Temperature for Magnetic Properties of Dysprosium Ferrite Nanoparticles

Dysprosium ferrite nanoparticles were prepared by the chemical co-precipitation method in the water phase system.The morphologies of particles were observed by transmission electron microscope（TEM）;The structure of products were characterized by X-ray diffraction（XRD）and the magnetic properties of sample were characterized by super-conducting quantum interference device（SQUID）.The effect of various temperatures on magnetic properties of the products were investigated in the range of 318~378 K.The TEM image and XRD pattern analysis revealed that the shape of magnetic particles is approximately spherical,with the average size about 18nm and cubic spinel structure.Saturation magnetization（M_S） of the products is 184.2mT at 318K,and MS of the magnetic nanoparticles decreases with increasing temperature.Coercitivity（H_C） of sample is 0.345mT at 318K and it decreases with increasing temperature,whereas superparamagnetic becomes more obvious.