基于蒙脱石层间域的二维纳米反应器属性,通过溶剂化作用,将氧化钛前躯体钛酸丁酯引入有机季铵盐阳离子插层的蒙脱石层间域中,并使其在蒙脱石层间域中水解、成核和相变结晶.采用XRD、原位升温Raman光谱、TEM分析手段研究了钛酸丁酯进入蒙脱石层间域过程,以及钛酸丁酯在蒙脱石层间域中水解和TiO2成核及相转变过程.结果表明钛酸丁酯成功进入了蒙脱石的层间域中,进入的量随作用时间的增加而增大;钛酸丁酯在蒙脱石层间域中水解生成无定形水合氧化钛,在150℃时开始形成锐钛矿结构的晶核,当焙烧温度达到500℃时,TiO2晶核结晶生成非常有序的锐钛矿结构;当焙烧温度达到700℃时,锐钛矿结构开始相转变为金红石结构,当温度达到1200℃时,锐钛矿相TiO2全部消失转变为金红石相TiO2.%Based on the two dimensional nanometer-reactor properties of interlayer spacing of montmoril-lonite,tetrabutyl titanate was introduced into the interlayer spacing of organic montmorillonite by solvent process.TiO2 was formed by using the interlayer spacing of montmorillonite as the reaction space.X-ray diffraction（XRD）,in situ temperature Raman spectroscopy and TEM were used to analyze the reaction and hydrolyzation process of tetrabutyl titanate,the process of nucleation and structural phase transition of TiO2 in the interlayer spacing of montmorillonite.The results showed that tetrabutyl titanate was successfully in-troduced into the interlayer space of montmorillonite.The amount of tetrabutyl titanate entering into the in-terlayer of montmorillonite increased with the adsorption time increasing.The tetrabutyl titanate hydrolyzed into amorphous hydrated titania in the interlayer of montmorillonite.Hydrated titania in the interlayer of montmorillonite began to form crystal nucleus which was anatase TiO2 structural crystal nucleus at 150 ℃.When the baking temperature up to 500 ℃,the TiO2 crystal nucleus crystallized into complete ordering anatase.The anatase was gradually transformed to rutile at the temperature of 700 ℃.The anatase phase was transformed to rutile phase completely with the baking temperature up to 1200 ℃.
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