摘要：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。 

关键词：纳米二氧化硅；化学沉淀法；单分散

Abstract：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 elec tron microscope were used to characterize the as-prepared particles. The re sults showed that the SiO₂ nano-particles with uniform distribution of grain size （50～90 nm），amorphous phase and regular spherical shape were ob tained by the optimal conditions，which the molar ratio of tetraethyl or thosilicate， ethanol and ammonia was 1:6:4. 

Keywords：SiO₂ nano-particles；chemical precipitation； mono-dispersion