多重射流燃烧反应制备的TiO_2/SiO_2纳米复合颗粒的形态和结构

Morphology and Structure of TiO_2 / SiO_2 Nanocomposites Prepared by Muti-jet Flame Reactor

气相燃烧合成纳米颗粒一般是指利用气体燃料提供高温反应区．通过物理或者化学过程从气溶胶中获得纳米颗粒的过程。相对于其它纳米材料合成方法而言，气相燃烧合成纳米颗粒的粒径小、纯度高．是制备纳米颗粒材料的重要方法．也是最有工业化前景的制备方法之一。人们已经利用气相燃烧法制备了SiO2、TiO2、SnO2、Al2O3、ZrO2、GeO2等纳米颗粒．实现了大规模的工业化生产。近年来，气相燃烧法制备纳米复合颗粒研究逐渐成为热点．

TiO2-SiO2 nanocomposite particles were prepared in premixed H2/Air flame, and the morphology and structure of these nanocomposites were characterized by FUR, XRD, TEM and HRTEM. The morphology of SiO2/ TiO2 nanocomposites was different from that of pure TiO2 or SiO2 nanoparticles, and the chemical bond of Ti-O-Si was found in the nanocomposites indicating that the TiO2/SiO2 nanocomposites were not merely a physical mixture of TiO2 and SiO2. TiO2 nanocrystalline grains with sizes of 1-2 nm were homogeneously dispersed in the amorphous SiO2 matrix when TIC14 and SIC14 were mixed at molecular level in the flame. The particle size and rutile content decreased with increasing of SiO2 molar ratio.