Preparation of Magnetic Fe2O3-SiO2 Mesoporous Nano-Composite Films Via Sol-Gel Process

Magnetic Fe2O3-SiO2 mesoporous nano-composite films were prepared by means of a two-step acid-catalyzed method and sol-gel process using tetraethoxysilane (TEOS) as the starting material, iron nitrate Fe(NO3)(3)center dot 9H(2)O as iron source material. A surfactant Cetyltrimethyl ammonium bromide (CTAB) is used as an organic template as the structure directing agent, under acidic conditions to generate the mesoporous structure upon removal by heat treatment. Mesoporous structure and magnetic characteristics of the films were investigated by Small angle X-ray diffraction and vibrating sample magnetometer (VSM). It is found that the saturation magnetization (M-s) of the films increases with the calcination temperature. The magnetization measurements reveal that magnetic Fe2O3-SiO2 mesoporous nano-composite films display normal ferromagnetic behaviors. It is also shown that the CTAB plays a key role in the magnetic properties of Fe2O3-SiO2 mesoporous nano-composite films. The SEM images exhibit a much more homogeneous morphology.