Nickel ferrite on silica nanocomposites prepared by the sol–gel method
Nickel ferrite on silica nanocomposites prepared by the sol–gel method
复制标题
溶胶-凝胶法制备二氧化硅纳米铁氧体复合材料
DOI：
10.1016/j.jmmm.2004.02.020
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Zhenhua Chen
中科院分区：
文献类型：
--
作者：
Xianghui Huang;Zhenhua Chen
以正硅酸乙酯为氧化硅前驱体，金属硝酸盐为铁氧体前驱体，成功地合成了镍铁氧体纳米粒子均匀分散在氧化硅基体中的纳米复合材料。用X射线衍射、差示扫描量热、红外光谱、透射电镜和振动样品磁强计对（NiFe 2 O 4）xSiO 2（1−X）（0.05 <$X <$0.55）样品进行了表征。结果表明，当X = 0.15时，材料具有非晶态特征;当X = 0.15时，随着浓度的增加，材料的晶粒尺寸从2 nm增加到25 nm，而在更高浓度下，观察到晶粒尺寸减小。磁性能与晶粒尺寸有很强的依赖性，Ms值随晶粒尺寸的增大而增大，在3.7 ~ 11 emu/g范围内，矫顽力可达313 Oe，是块体镍铁氧体矫顽力的4倍多。
Nanocomposites with nickel ferrite nanoparticles uniformly dispersed in silica matrix were successfully synthesized using tetraethoxysilane as a precursor of silica and metallic nitrates as precursors of ferrite. The obtained (NiFe2O4)XSiO2(1−X)(0.05⩽X⩽0.55) samples were investigated by X-ray diffraction, differential scanning calorimetry, infrared spectroscopy, transmission electron microscopy and vibration sample magnetometer. The results show that for X⩽0.15 the materials have an amorphous character and for 0.15⩽X⩽0.50 the crystalline sizes ranging from 2 to 25nm increase with increasing concentration, while at higher concentrations, a decrease in the crystalline sizes is observed. The magnetic properties exhibit a strong dependence on the crystalline size, Msvalues increase with the crystalline size ranged from 3.7 to 11emu/g and coercivity can get value as high as 313Oe, which is more than four times higher than the coercivity of bulk nickel ferrite.