TiOCl2溶液合成异形TiO2纳米粉及形成机理研究

Study on Preparation and Formation Mechanism of Nanophase TiO2 with Different Morphologies and Crystalline- structures from TiOCl2 Solution

以TiOCl2溶液为前驱物,由室温至180℃直接反应均可获得TiO2纳米晶.当反应温度低于70℃,100℃和160℃时,沉淀粒子的形貌分别为针形聚集体、球型和针形单晶.相应反应温度下所得沉淀的晶型分别为金红石型、混晶和金红石型.晶体的形貌和粒子的均一性强烈依赖于反应温度和成核与成长速率.详细讨论了TiOCl2溶液在各个温区的水解及TiO2粒子的形成机理.

Nanocrystal TiO2 was prepared from the precursor TiOCl2 at temperatures ranging from room temperature to 180 degreesC. The morphologies of precipitated particles were needle - shaped agglomerates (rutile), sphere - shaped (mixed crystad), or needle - shaped single crystals (rutile) when the reaction temperature was lower than 70 degreesC, 100 degreesC and 160 degreesC respectively. The crystal morphology and particle uniformity were intensely dependent on the reaction conditions such as temperature, rate of nucleation and growth. The mechanism of TiO2 formation at various temperatures is discussed in detail.