Microstructure and Magnetic Properites of Nanocomposites with Iron Nanoparticles Supported by Porous Alumina

Porous alumina supported iron composites were prepared through impregnation-reduction process.The phase identification and structural analysis of the samples were examined by X-ray diffraction technique,while the magnetic properties of the nanocomposites were investigated by vibrating sample magnetometer(VSM) and 57Fe Mssbauer spectrometry.It was found that iron elements exist in the form of iron nanoparticles and superparamagnetic α-Fe2O3( 20 nm).From the 57Fe Mssbauer spectra,we found that after calination under hydrogen atmosphere at 600 ℃ for 3 h,59.9% iron elements changed into iron.Porous magnetic composites with various compositons,microstructures and magnetic properties can be prepared through impregnation-reduction prodecure.