由钛酸盐纳米带水热制备锐钛矿型TiO2纳米带

研究了水热处理具有层状结构的钛酸钠纳米带或钛酸纳米带转化为锐钛矿型TiO₂的制备过程、难易程度和相转化机理. 实验结果表明, 当水热反应温度和时间分别在160 ℃ 和24 h以内, 钛酸钠纳米带很难完全转化为锐钛矿型TiO₂, 若升高反应温度并延长反应时间, 则可制得纯的锐钛矿型TiO₂, 但纳米带形貌被严重破坏; 当水热反应温度和时间分别为160 ℃ 和16 h时, 1次酸洗的钛酸纳米带能够完全转化为锐钛矿型TiO₂, 若钛酸纳米带经过3次强酸浸泡, 则在160 ℃下相转化时间就会缩短到12 h, 所有钛酸纳米带在转化为TiO₂后的形貌仍为纳米带, 但经3次酸浸后生成的TiO₂纳米带表面更光滑. 讨论了钛酸钠纳米带或钛酸纳米带转化为锐钛矿型TiO₂的相转化机理.

Anatase TiO2 Nanobelts Prepared Hydrothermally from Titanate Nanobelts

Preparation process and phase-transformation mechanism of anatase TiO2 from sodium titanate or hydrogen titanate nanobelts were studied with various measurement techniques. The results show that it is difficult for sodium titanate nanobelts to transform into anatase TiO2 below the reaction temperature of 160 ℃ and the reaction time of 24 h, whereas pure anatase TiO2 without the morphology of nanobelts can be obtained under the higher reaction temperature and the longer reaction time. The pure anatase TiO2 nanobelts can also be prepared from hydrogen titanate by immersed into strong acid for one time at 160 ℃ for 16 h, after immersing into acid for three times, the pure anatase TiO2 nanobelts can be prepared at 160 ℃ for 12 h. The transformation mechanism from sodium titanate or hydrogen titanate nanobelts to anatase TiO2 was also discussed.