Abstract: A nanometer composite powder was prepared with nanometer TiO₂ encapsulated with  SiO₂ film which was formed by hydrolyzation of NNa₂SiO₃ with the method of heterogeneous analysis renucleation. The FT-IR, SEM, particle size, BET surface area test and XPS sults verified the exist of a homogenous and compact coating on the surface of TiO₂ particle and bounded by Ti-O-Si bond. The dispersing test indicated that the disperse properties of the composite powder was improvrd greatly.

Key words: nano-TiO₂ coat, nano-SiO₂ , composite powder, heterogeneous-nucleation

摘要： 以 Na₂SiO₃为原料，采用非均匀成核法在纳米 TiO₂ 基体上制备了  SiO₂ 表面保护膜层，通过红外光谱、X射线光电子能谱、扫描电镜、粒径测量、BET比表面积测量分析，证实纳米 TiO₂ 颗粒表面包覆了一层均匀致密的  SiO₂纳米膜，而且两者是以化学键合方式结合在一起。分散性能测试表明：纳米 SiO₂ ／TiO₂复合粉体的分散性能明显提高。

关键词: 纳米 TiO₂；包覆；纳米  , SiO₂；复合粉体；非均匀成核