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以TiCl_4和金红石型TiO_2纳米晶为原料,采用晶种诱导水热法合成出不同粒径和形貌的纳米TiO_2。采用X射线衍射仪、透射电镜和BET氮吸附比表面仪对所得样品进行了表征。研究了晶种用量、反应温度、反应时间对TiO_2微观结构的影响。结果表明,添加晶种后,溶液中的Ti~(4+)优先在TiO_2晶种表面生长形成纳米棒,当Ti~(4+)消耗殆尽时,TiO_2的生长变为“溶解-结晶”过程。随着反应温度的升高和时间的延长,TiO_2由纳米微晶的聚集体变为纳米棒的聚集体,其晶粒尺寸逐渐变大,长径比和比表面积变小。
TiCl_4 and rutile TiO_2 nanocrystals were used as raw materials to synthesize nano-TiO_2 with different size and morphology by using seed-induced hydrothermal method. The obtained samples were characterized by X-ray diffraction, transmission electron microscopy and BET nitrogen adsorption surface area analyzer. The effects of the amount of seed, the reaction temperature and the reaction time on the microstructure of TiO 2 were investigated. The results show that Ti 4+ preferentially grows on the surface of TiO 2 seed crystals to form nanorods when the seed crystals are added. When the Ti 4+ depletes, the growth of TiO 2 becomes “dissolution-crystallization” "process. With the increase of reaction temperature and the extension of time, TiO_2 changed from aggregates of nanocrystals into aggregates of nanorods. The grain size of TiO_2 became larger and the aspect ratio and specific surface area became smaller.