纳米氧化钛团聚结构的研究

爆轰形成的高温、高压持续时间短,使得新生的氧化钛来不及长成较大的晶粒,只能形成大量的类球形纳米微粒。在潮湿的爆生气体环境中,这些纳米氧化钛颗粒间的相互作用(如碰撞、摩擦、挤压、渗透和粘附等)比较剧烈,极易聚集成团聚体。初步分析了以硫酸氧钛为钛源、采用爆轰法合成的纳米氧化钛的团聚结构和分散形态,对经过加热至500℃、保温1 h热处理后的纳米氧化钛的团聚结构也进行了分析。研究结果表明:用爆轰法合成的纳米氧化钛存在软团聚和硬团聚两种形式,而经过热处理(500℃、1 h)的纳米氧化钛的团聚程度得到了一定的改善。此外,还分析了纳米粉体的特性、爆轰特点和爆生气体环境等因素对产生纳米氧化钛团聚结构的影响。

Study on the Agglomerate Structures of TiO2 Nanoparticles

The short duration of high temperature and high pressure during the detonation process made the TiO₂ nanoparticles not have enough time to grow into large and fine crystallites and only generate a large number of spherical-like nanoparticles. The rapid interactions between these formed TiO₂ nanoparticles (such as collision, friction, extrusion, infiltration and adhesion) could easily form agglomerate structures in the humid detonation gas environment. The agglomerate structures and dispersion morphologies of the TiO₂ nanoparticles prepared by detonation method using titanium titanyl sulfate as TiO₂ source were studied. In order to reveal the influence of heat treatment on the agglomeration properties of the TiO₂ nanoparticles, the agglomerate structures of the TiO₂ nanoparticles via heat treatment at 500 ℃ for 1 h were also analyzed. Research showed that the soft and hard agglomerates of the TiO₂ nanoparticles were formed and that the agglomerate structures of the TiO₂ nanoparticles after heat treatment could be improved to some extent. The influences of nanoparticle characteristics, detonation characteristics and detonation gas environment on the formation of the agglomerate structures of TiO₂ nanoparticles were also discussed.