正交试验优化核壳型Fe_3O_4@SiO_2磁性复合微球的制备工艺

Orthogonal Design of Synthesis Conditions of Core-shell Fe_3O_4@SiO_2 Composite Microballoons

采用共沉淀法和溶胶-凝胶法制备了磁性Fe3O4纳米粒子及核壳型Fe3O4@SiO2复合微球,利用红外光谱(FTIR)技术测定了微球表面基团,证明了SiO2确实在Fe3O4纳米粒子的表面形成了包覆层。通过正交试验设计,利用激光粒度仪测量的微球粒径为指标,考察TEOS与磁性微球的体积比、反应温度、反应时间和乙醇浓度四因素对微球粒径的影响。结果表明TEOS与磁性微球的体积比为2、反应温度为80℃、反应时间为4 h,乙醇浓度为80%是制备大粒径Fe3O4@SiO2磁性复合微球的适宜条件。

Magnetic Fe3O4 nanoparticles were prepared with coprecipitation method, and then the core -shell Fe3 04 @ SiO2 composite microballoons were synthesized with sol - gel technique. The surface group of the both particles were measured by means of fourier transform infrared Spectroscopy （FFIR） , the result showed that SiO2 was successfully prepared on the surface of Fe3O4 nanoparticle. On the basis of orthogonal design, experiments on the investigation of the effect of 4 factors： the ratio of TEOS/magnetic Fe304 nanoparticles, treating temperature and time, and ethyl alocohol concentration were carried out, and the particle diameter obtained from laser particle sizer was set as the index. The results demonstrated that in 80% ethanol/water solution, TEOS/magnetic Fe3O4 nanoparticles （with a ratio of 2 ： 1 ） for 2 h at 80℃ was suitable to modify the surface of Fe3O4@ SiO2 composite mieroballoons.