کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
74685 | 49097 | 2010 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Synthesis and magnetic properties of CoFe2O4 nanoparticles confined within mesoporous silica Synthesis and magnetic properties of CoFe2O4 nanoparticles confined within mesoporous silica](/preview/png/74685.png)
We report here the synthesis and magnetic properties of cobalt ferrite (CoFe2O4) nanoparticles inside the nanoscale channels of highly ordered mesoporous silica SBA-15. Formation of CoFe2O4 nanoparticles inside the mesoporous channels was realized by impregnation of cobalt salt and iron salt precursors into the channels of the SBA-15, followed by calcination at different temperatures (400–1000 °C) in air. The products were characterized by X-ray diffraction (XRD), field emission scanning and transmission electron microscopies (FESEM and TEM), and nitrogen adsorption–desorption isotherm measurements. As per results, a typical characteristic of the obtained materials is that the mesoporous channels of SBA-15 are partially filled by CoFe2O4 nanocrystallites. In consequence, these materials exhibit open, ordered 2D hexagonal frameworks, which are very similar to that of the pristine SBA-15 except for the reduced dimension and specific surface area. Magnetic properties of the obtained materials show strong dependence on the calcination temperature. The maximum-value combination of the saturation magnetization (Ms), the remnant magnetization (Mr) and the coercivity (Hc) is obtained from the sample prepared at 1000 °C. Moreover, compared with the pure CoFe2O4 powder prepared at the same temperature, the CoFe2O4 incorporated SBA-15 composite possess higher magnetic parameters (Ms, Mr and Hc).
Journal: Microporous and Mesoporous Materials - Volume 135, Issues 1–3, November 2010, Pages 137–142