【摘要】 以正硅酸乙酯及铁盐为原料,通过溶胶-凝胶法制备γ-Fe2O3/SiO2纳米复合粉体。采用红外吸收光谱、X射线衍射仪、透射电镜及振动样品磁强计等对复合粉体进行表征。结果表明:以不同铁盐为前驱体得到不同晶型的Fe2O3;不同酸对磁性复合粉体的性能有重要影响:加硝酸时,γ-Fe2O3大小为15nm,其饱和磁化强度大;加入醋酸时得到的γ-Fe2O3颗粒为5nm,且粒度分布变窄,但其饱和磁化强度明显下降;并对γ-Fe2O3在SiO2中的合成机理进行了探讨。更多还原

【Abstract】 γ-Fe2O3/SiO2 nanocomposites were prepared via sol-gel processing using tetraethylorthosilicate and ferric salt as starting materials. The particle size and properties of γ-Fe2O3/SiO2 nanocomposites were studied by transmission electron microscopy,X-ray diffraction,Fourier Transform Infrared Spectroscopy and vibrating sample magnetometer. The influence of different precursors on the iron oxide was studied. Different acids added during the preparation play an important role on the properties of γ-Fe2O3/SiO2 nanocomposites. That is,the size of the obtained γ-Fe2O3 nanoparticles is enlarged and the saturation magnetization is increased as nitric acid added. When the acetic acid is used,the size of the obtained γ-Fe2O3 nanoparticles is reduced,the particle size distribution is narrowed and the saturation magnetization is lowered. The reaction mechanism of the γ-Fe2O3 embedded in SiO2 was investigated.更多还原