纳米氧化钛团聚结构的研究

Study on the Agglomerate Structures of TiO_2 Nanoparticles

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。

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.