单分散纳米二氧化硅的制备

以正硅酸乙酯为原料,氨水为催化剂,采用化学沉淀法,通过合理地控制反应条件,制备了单分散球形纳米二氧化硅颗粒。通过激光粒度分析、X射线衍射及透射电镜等测试手段对制备的二氧化硅颗粒进行表征。结果表明:当最佳试验条件为正硅胶乙酯与乙醇、氨水的物质的量为1∶6∶4,表面活性剂的添加量为3%时,制备的纳米氧化硅粒度分布均匀,且呈规则的球形,粒径为50~90 nm,为无定形态二氧化硅。

Preparation of Monodispersed SiO2 Nano-particles

The mono-dispersed SiO2 nano-particles were prepared by chemical precipitation.The tetraethyl orthosilicate(TEOS) was adopted as rough material and the ammonia liquor(NH4OH) was served as catalytic agent.Laser particle size analyzer,X-ray diffraction and transmission electron microscope were used to characterize the as-prepared particles.The results showed that the SiO2 nano-particles with uniform distribution of grain size(50～90 nm),amorphous phase and regular spherical shape were obtained by the optimal conditions,which the molar ratio of tetraethyl orthosilicate,ethanol and ammonia was 1:6:4.