氧气含量比变化对气相爆轰合成纳米二氧化钛的影响

Influence of Oxygen Concentration on TiO2 Nanoparticles Prepared by Gaseous Detonation

以氢气和氧气作为爆炸源,四氯化钛作为前躯体气相爆轰制备纳米二氧化钛是一种新兴的纳米氧化物制备方法。通过X射线衍射(XRD)分析其晶相组成,并通过透射电镜(TEM)观察了产物颗粒的大小和形貌,总结了氧气含量对产物的影响。结果表明,在一定条件下产生了金红石相和锐钛矿相的混合晶。随着氧气含量的增加,混合物中锐钛矿相的相对含量变大,但是,氧气含量足够时,生成的是中间产物和金红石相的混合粉体。颗粒呈球形(或类球形),颗粒尺寸变大(80～100nm),分散性变好,颗粒变得更均匀。

TiO2 nanoparticles prepared by gaseous detonation which use hydrogen-oxygen gas mixture as the explosion source and the titanium tetrachloride as the precursor is a new method. The crystal composition, grain size and phase structure were studied by the methods of XRD and TEM, and ana- lyzed the oxygen content on the influence of the product. The result shows that the rutile and anatase mixed crystal were obtained under certain conditions. The relative content of anatase grows as the ox ygen content increases, but the mixed powder becomes intermediate product and rutile when the oxy gen concent high enough. The grain are mostly spherical （or spherical） ,the grain dimension becomes bigger （about 80-100nm）, the grain dispersivity is better and the grain becomes more uniform.