氧化硅包裹四氧化三铁微球的制备及表征

Preparation and Characterization of Silica-coated Fe_3O_4 Nanoparticles

在室温下,采用H2O2氧化Fe(OH)2悬浮液的方法制备得到了粒径23nm左右的磁性纳米粒子,经X射线衍射检测制备得到的是Fe3O4磁性纳米粒子,粒子的饱和磁化强度为59.05emu/g。先用硅烷偶联剂KH560修饰Fe3O4,提高粒子在乙醇溶液中的单分散性,在此基础上采用溶胶凝胶法通过TEOS水解制备得到分散性佳、尺寸均匀、粒径为25nm左右核壳结构的氧化硅包覆Fe3O4纳米粒子的磁微球。

Fe3O4 nanoparticles were synthesized from an aqueous Fe（OH）2 suspension by oxidizing with H2O2 at 25℃. The nanoparticles are characterized through X-Ray Diffraction, the Vibrating Sample Magnetometer （VSM） and transmission electron microscope （TEM）. The results show the average diameter of 23nm and the saturation magnetization of 59.06emu/g. The Fe3O4 nanoparticles first modified by KH560 to enhance the monodispersity in C2 H5 OH, and then treated with TEOS to prepare the Fe3O4/SiO2 core/shell composite nanoparticles which were well dispersed and with uniform size around 25nm.