Preparation of Fe3O4 Film by in-situ Oxidative Hydrolysis on Chitosan

The Fe3O4 films were prepared by in-situ oxidative hydrolysis on chitosan. The structures and characteristics of the prepared Fe3O4 films were investigated by X-ray diffractometry (XRD), scanning electron microscopy (SEM), atom force microscopy (AFM), vibrating sample magnetometry (VSM) and thermogravimetric-differential thermal analysis (TG-DTA). The results show that, (1) the as-synthesized Fe3O4 films are pure Fe3O4 with cubic inverse spinel structure; (2) the network structured film can be obtained at lower temperature, and the compact particle film at higher temperature; (3) the prepared Fe3O4 films are super-paramagnetic, and the saturation magnetization is improved with increasing the reaction temperature, which is 49.03 emu/g at 80℃;(4) the temperature of phase transformation from Fe3O4 to α-Fe2O3 is about 495℃. Besides, the formation mechanism of Fe3O4 film was also proposed.